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CLI reference

Qubit design

Fluxus v0 command line: analytic cQED oracle, QEM surrogate, frequency-collision yield Monte Carlo, inverse design, and the process registry. v0 numbers come from closed-form physics, not an EM solver. The CLI runs the engine in-process: no server and no key.

Exit codes

  • 0answered (abstained answers included, flagged)
  • 2bad input
  • 3refused: outside the data, or the engine is not available

fluxus qem

also ham

predict Hamiltonian parameters for one design cell

Predict f01, anharmonicity, fr, g and chi for one qubit-resonator cell. Uses the trained QEM surrogate with conformal intervals when its checkpoint and calibration residuals exist; otherwise falls back to the analytic oracle and says so. Out-of-envelope inputs exit 0 but are marked abstained.

usage
fluxus qem [-h] [--pad-width-um X] [--pad-height-um X] [--pad-gap-um X] [--ground-gap-um X] [--lj-nh X] [--length-um X] [--center-width-um X] [--gap-um X] [--eps-r X] [--coupling-cap-ff X] [--kind {lambda4,lambda2}] [--alpha A] [--json]

Arguments

--pad-width-um X
transmon pad width, um (default 400)type float (finite)
--pad-height-um X
transmon pad height, um (default 80)type float (finite)
--pad-gap-um X
gap between the two transmon pads, um (default 30)type float (finite)
--ground-gap-um X
pad edge to ground plane, um (default 30)type float (finite)
--lj-nh X
Josephson inductance, nH (default 12)type float (finite)
--length-um X
readout resonator length, um (default 4000)type float (finite)
--center-width-um X
CPW center-trace width, um (default 10)type float (finite)
--gap-um X
CPW gap, um (default 6)type float (finite)
--eps-r X
substrate relative permittivity (default 11.45, silicon)type float (finite)
--coupling-cap-ff X
qubit-resonator coupling capacitance, fF (default 5)type float (finite)
--kind
resonator kind (default lambda4; lambda2 is outside the trained envelope, so the surrogate abstains)one of lambda4, lambda2
--alpha A
miscoverage level for conformal intervals (default 0.1, i.e. 90% intervals)type float (finite) · default 0.1
--json
print machine-readable JSON to stdoutflag
example
fluxus qem --pad-gap-um 30 --lj-nh 12 --length-um 4500 --coupling-cap-ff 5 --json
Same answer asPOST/v1/fluxus/qem

fluxus qem-cross

Hamiltonian for a TransmonCross cell (SQuADDS geometry)

Predict f01, anharmonicity, fr, g and chi for one TransmonCross + claw cell -- the geometry family qiskit-metal and SQuADDS use. Geometry -> capacitance is trained on Ansys HFSS; capacitance -> Hamiltonian is exact. NOT validated against silicon. This is a DIFFERENT geometry family from fluxus qem, which takes parallel-pad dimensions; the two are not interchangeable. Off-envelope input REFUSES (exit 3) rather than extrapolating.

usage
fluxus qem-cross [-h] [--cross-length-um X] [--claw-length-um X] [--ground-spacing-um X] [--junction-lj-nh X] [--cross-gap-um X] [--cross-width-um X] [--claw-width-um X] [--claw-gap-um X] [--length-um X] [--coupling-length-um X] [--center-width-um X] [--gap-um X] [--eps-r X] [--claw-cpw-length-um X] [--finger-length-um X] [--cap-gap-um X] [--cap-width-um X] [--kind {lambda4,lambda2}] [--finger-count N] [--squid-lj1-nh X] [--squid-lj2-nh X] [--flux-bias-phi0 X] [--flux-noise-uphi0 X] [--flux-noise-f-ir-hz X] [--flux-noise-t-us X] [--body JSON|PATH] [--intervals] [--alpha ALPHA] [--purcell-filter-suppression X] [--json]

Arguments

--cross-length-um X
cross arm length, um (swept 90 to 420)type float (finite)
--claw-length-um X
claw length, um (swept 70 to 400; at most cross - 20)type float (finite)
--ground-spacing-um X
claw ground spacing, um (4.1 to 5.0 or 9.1 to 10.0)type float (finite)
--junction-lj-nh X
Josephson inductance, nH (free; sets EJ)type float (finite)
--cross-gap-um X
pinned at 30.0 by the HFSS configtype float (finite)
--cross-width-um X
pinned at 30.0type float (finite)
--claw-width-um X
pinned at 15.0type float (finite)
--claw-gap-um X
pinned at 5.1type float (finite)
--length-um X
resonator length, um (lambda4 2700 to 4700)type float (finite)
--coupling-length-um X
readout coupler length, um (lambda4 100 to 500)type float (finite)
--center-width-um X
CPW centre width, um (trained value 11.7)type float (finite)
--gap-um X
CPW gap, um (trained value 5.1)type float (finite)
--eps-r X
substrate permittivity (pinned at 11.45)type float (finite)
--claw-cpw-length-um X
claw stub, um (default 40, every HFSS row; another value is answered and flagged)type float (finite)
--finger-length-um X
lambda2 NCap finger length, um (15.9 to 60.9)type float (finite)
--cap-gap-um X
lambda2 NCap finger gap, um (1.1 to 6.1)type float (finite)
--cap-width-um X
lambda2 NCap finger width, um (4.9 to 14.9)type float (finite)
--kind
resonator kind (default lambda4)one of lambda4, lambda2
--finger-count N
lambda2 NCap finger count (1 to 10)type int
--squid-lj1-nh X
SQUID junction 1 inductance, nHtype float (finite)
--squid-lj2-nh X
SQUID junction 2 inductance, nHtype float (finite)
--flux-bias-phi0 X
flux bias, Phi0 (-1 to 1; default 0)type float (finite)
--flux-noise-uphi0 X
1/f flux-noise amplitude at 1 Hz, uPhi0/sqrt(Hz); given, a first-order dephasing estimate is addedtype float (finite)
--flux-noise-f-ir-hz X
infrared cut-off, Hz (default 1)type float (finite)
--flux-noise-t-us X
dephasing time scale, us (default 10)type float (finite)
--body JSON|PATH
base request: a JSON object or a .json file; flags override its fields
--intervals
90% intervals on every output (against HFSS)flag
--alpha
interval miscoverage (default 0.1)type float (finite)
--purcell-filter-suppression X
your measured Purcell filter factor, >= 1type float (finite)
--json
print the exact API body as JSONflag
example
fluxus qem-cross --cross-length-um 310 --claw-length-um 160 --junction-lj-nh 11.3 --json
Same answer asPOST/v1/fluxus/qem/cross

fluxus yld

frequency-collision yield Monte Carlo for a chip

Monte Carlo yield for a fixed-frequency chip: sample post-fab frequency scatter and count chips with no violation of the seven Hertzberg et al. (arXiv:2009.00781) collision conditions.

usage
fluxus yld [-h] --n-qubits N [--lattice {heavy_hex,square}] [--sigma-f-mhz S] [--anharm-mhz A] [--n-trials N] [--seed S] [--json]

Arguments

--n-qubits Nrequired
number of qubits on the chiptype int
--lattice
coupling lattice (default heavy_hex)one of heavy_hex, square · default heavy_hex
--sigma-f-mhz S
post-fab frequency spread, 1-sigma MHz (default 12)type float (finite) · default 12
--anharm-mhz A
transmon anharmonicity, MHz (default -300)type float (finite) · default -300
--n-trials N
Monte Carlo trials (default 20000)type int · default 20000
--seed S
random seed for reproducible runstype int
--json
print machine-readable JSON to stdoutflag
example
fluxus yld --n-qubits 127 --lattice heavy_hex --sigma-f-mhz 12 --n-trials 20000 --json
Same answer asPOST/v1/fluxus/yld

fluxus inv

inverse design: target parameters to ranked cell candidates

Search SPEC_RANGES for cells whose verified Hamiltonian parameters match the targets. The surrogate (or oracle) proposes and refines candidates; finalists are always re-solved with the analytic oracle and ranked by weighted normalized distance. Impossible targets do not fail; the distance reports the gap honestly. Valid target names: f01_ghz, anharmonicity_mhz, fr_ghz, g_mhz, chi_mhz.

usage
fluxus inv [-h] --target NAME=VALUE [--tolerance NAME=VALUE] [--n-candidates N] [--n-screen N] [--seed S] [--json | --csv]

Arguments

--target NAME=VALUErequired
desired parameter, repeatable (e.g. --target f01_ghz=4.8)repeatable
--tolerance NAME=VALUE
per-target distance scale in the same unit, repeatable; distance 1.0 then means 'off by one tolerance on average'repeatable
--n-candidates N
number of candidates to return (default 5)type int · default 5
--n-screen N
screening population size (default 2048)type int · default 2048
--seed S
random seed for a deterministic searchtype int
--json
print machine-readable JSON to stdoutflag
--csv
print candidates as CSV rowsflag

Not together: json / csv.

example
fluxus inv --target f01_ghz=4.8 --target fr_ghz=7.0 --json
Same answer asPOST/v1/fluxus/inv

fluxus verify

compare the surrogate prediction with the oracle for one cell

Run the surrogate prediction and the analytic-oracle verification for the same cell and print the per-target delta (predicted minus verified). When conformal intervals are available, also report whether the verified value falls inside each interval. Without a trained checkpoint the prediction falls back to the oracle and the delta is zero by construction.

usage
fluxus verify [-h] [--pad-width-um X] [--pad-height-um X] [--pad-gap-um X] [--ground-gap-um X] [--lj-nh X] [--length-um X] [--center-width-um X] [--gap-um X] [--eps-r X] [--coupling-cap-ff X] [--kind {lambda4,lambda2}] [--alpha A] [--json]

Arguments

--pad-width-um X
transmon pad width, um (default 400)type float (finite)
--pad-height-um X
transmon pad height, um (default 80)type float (finite)
--pad-gap-um X
gap between the two transmon pads, um (default 30)type float (finite)
--ground-gap-um X
pad edge to ground plane, um (default 30)type float (finite)
--lj-nh X
Josephson inductance, nH (default 12)type float (finite)
--length-um X
readout resonator length, um (default 4000)type float (finite)
--center-width-um X
CPW center-trace width, um (default 10)type float (finite)
--gap-um X
CPW gap, um (default 6)type float (finite)
--eps-r X
substrate relative permittivity (default 11.45, silicon)type float (finite)
--coupling-cap-ff X
qubit-resonator coupling capacitance, fF (default 5)type float (finite)
--kind
resonator kind (default lambda4; lambda2 is outside the trained envelope, so the surrogate abstains)one of lambda4, lambda2
--alpha A
miscoverage level for conformal intervals (default 0.1)type float (finite) · default 0.1
--json
print machine-readable JSON to stdoutflag
example
fluxus verify --lj-nh 14 --length-um 5000

fluxus qubit

qubit design: TransmonCross and parallel-pad cells, inverse design, GDS, junction, yield

The qubit-design API on the command line: every command answers exactly what its /api route answers (--json prints that body). Exit 0 answered, 2 bad input, 3 refused. HFSS-trained or analytic; nothing here is silicon.

usage
fluxus qubit [-h] command ...

Commands

fluxus qubit schema

fields, units, defaults, envelopes, engines

usage
fluxus qubit schema [-h] [--json]

Arguments

--json
print the exact API body as JSONflag
example
fluxus qubit schema --json
Same answer asGET/v1/fluxus/qem/schema

fluxus qubit status

whether each engine loads here

usage
fluxus qubit status [-h] [--json]

Arguments

--json
print the exact API body as JSONflag
example
fluxus qubit status
Same answer asGET/v1/fluxus/qem/status

fluxus qubit cross

Hamiltonian, kappa and Purcell for a TransmonCross cell

usage
fluxus qubit cross [-h] [--cross-length-um X] [--claw-length-um X] [--ground-spacing-um X] [--junction-lj-nh X] [--cross-gap-um X] [--cross-width-um X] [--claw-width-um X] [--claw-gap-um X] [--length-um X] [--coupling-length-um X] [--center-width-um X] [--gap-um X] [--eps-r X] [--claw-cpw-length-um X] [--finger-length-um X] [--cap-gap-um X] [--cap-width-um X] [--kind {lambda4,lambda2}] [--finger-count N] [--squid-lj1-nh X] [--squid-lj2-nh X] [--flux-bias-phi0 X] [--flux-noise-uphi0 X] [--flux-noise-f-ir-hz X] [--flux-noise-t-us X] [--body JSON|PATH] [--intervals] [--alpha ALPHA] [--purcell-filter-suppression X] [--json]

Arguments

--cross-length-um X
cross arm length, um (swept 90 to 420)type float (finite)
--claw-length-um X
claw length, um (swept 70 to 400; at most cross - 20)type float (finite)
--ground-spacing-um X
claw ground spacing, um (4.1 to 5.0 or 9.1 to 10.0)type float (finite)
--junction-lj-nh X
Josephson inductance, nH (free; sets EJ)type float (finite)
--cross-gap-um X
pinned at 30.0 by the HFSS configtype float (finite)
--cross-width-um X
pinned at 30.0type float (finite)
--claw-width-um X
pinned at 15.0type float (finite)
--claw-gap-um X
pinned at 5.1type float (finite)
--length-um X
resonator length, um (lambda4 2700 to 4700)type float (finite)
--coupling-length-um X
readout coupler length, um (lambda4 100 to 500)type float (finite)
--center-width-um X
CPW centre width, um (trained value 11.7)type float (finite)
--gap-um X
CPW gap, um (trained value 5.1)type float (finite)
--eps-r X
substrate permittivity (pinned at 11.45)type float (finite)
--claw-cpw-length-um X
claw stub, um (default 40, every HFSS row; another value is answered and flagged)type float (finite)
--finger-length-um X
lambda2 NCap finger length, um (15.9 to 60.9)type float (finite)
--cap-gap-um X
lambda2 NCap finger gap, um (1.1 to 6.1)type float (finite)
--cap-width-um X
lambda2 NCap finger width, um (4.9 to 14.9)type float (finite)
--kind
resonator kind (default lambda4)one of lambda4, lambda2
--finger-count N
lambda2 NCap finger count (1 to 10)type int
--squid-lj1-nh X
SQUID junction 1 inductance, nHtype float (finite)
--squid-lj2-nh X
SQUID junction 2 inductance, nHtype float (finite)
--flux-bias-phi0 X
flux bias, Phi0 (-1 to 1; default 0)type float (finite)
--flux-noise-uphi0 X
1/f flux-noise amplitude at 1 Hz, uPhi0/sqrt(Hz); given, a first-order dephasing estimate is addedtype float (finite)
--flux-noise-f-ir-hz X
infrared cut-off, Hz (default 1)type float (finite)
--flux-noise-t-us X
dephasing time scale, us (default 10)type float (finite)
--body JSON|PATH
base request: a JSON object or a .json file; flags override its fields
--intervals
90% intervals on every output (against HFSS)flag
--alpha
interval miscoverage (default 0.1)type float (finite)
--purcell-filter-suppression X
your measured Purcell filter factor, >= 1type float (finite)
--json
print the exact API body as JSONflag
example
fluxus qubit cross --cross-length-um 240 --claw-length-um 215 --ground-spacing-um 10 --junction-lj-nh 9.686 --length-um 3900 --coupling-length-um 225 --intervals
Same answer asPOST/v1/fluxus/qem/cross

fluxus qubit batch

many TransmonCross cells from a file

One design per line of .jsonl, an array (or {items}) in .json, or a row of .csv with /api/qem/cross field names as the header. Writes one result per design: jsonl (the exact slot) or csv.

usage
fluxus qubit batch [-h] [--intervals] [--alpha ALPHA] [-o PATH] [--format {jsonl,csv}] file

Arguments

FILE
--intervals
intervals for items that do not set themflag
--alpha
type float (finite)
-o, --output PATH
--format
one of jsonl, csv
example
fluxus qubit batch designs.csv -o out.csv
Same answer asPOST/v1/fluxus/qem/cross/batch

fluxus qubit sweep

one or two TransmonCross fields over a grid

usage
fluxus qubit sweep [-h] [--cross-length-um X] [--claw-length-um X] [--ground-spacing-um X] [--junction-lj-nh X] [--cross-gap-um X] [--cross-width-um X] [--claw-width-um X] [--claw-gap-um X] [--length-um X] [--coupling-length-um X] [--center-width-um X] [--gap-um X] [--eps-r X] [--claw-cpw-length-um X] [--finger-length-um X] [--cap-gap-um X] [--cap-width-um X] [--kind {lambda4,lambda2}] [--finger-count N] [--squid-lj1-nh X] [--squid-lj2-nh X] [--flux-bias-phi0 X] [--flux-noise-uphi0 X] [--flux-noise-f-ir-hz X] [--flux-noise-t-us X] [--body JSON|PATH] --field {cross_length_um,claw_length_um,ground_spacing_um,junction_lj_nh,length_um,coupling_length_um} --start START --stop STOP [--n N] [--field2 {cross_length_um,claw_length_um,ground_spacing_um,junction_lj_nh,length_um,coupling_length_um}] [--start2 START2] [--stop2 STOP2] [--n2 N2] [--json]

Arguments

--cross-length-um X
cross arm length, um (swept 90 to 420)type float (finite)
--claw-length-um X
claw length, um (swept 70 to 400; at most cross - 20)type float (finite)
--ground-spacing-um X
claw ground spacing, um (4.1 to 5.0 or 9.1 to 10.0)type float (finite)
--junction-lj-nh X
Josephson inductance, nH (free; sets EJ)type float (finite)
--cross-gap-um X
pinned at 30.0 by the HFSS configtype float (finite)
--cross-width-um X
pinned at 30.0type float (finite)
--claw-width-um X
pinned at 15.0type float (finite)
--claw-gap-um X
pinned at 5.1type float (finite)
--length-um X
resonator length, um (lambda4 2700 to 4700)type float (finite)
--coupling-length-um X
readout coupler length, um (lambda4 100 to 500)type float (finite)
--center-width-um X
CPW centre width, um (trained value 11.7)type float (finite)
--gap-um X
CPW gap, um (trained value 5.1)type float (finite)
--eps-r X
substrate permittivity (pinned at 11.45)type float (finite)
--claw-cpw-length-um X
claw stub, um (default 40, every HFSS row; another value is answered and flagged)type float (finite)
--finger-length-um X
lambda2 NCap finger length, um (15.9 to 60.9)type float (finite)
--cap-gap-um X
lambda2 NCap finger gap, um (1.1 to 6.1)type float (finite)
--cap-width-um X
lambda2 NCap finger width, um (4.9 to 14.9)type float (finite)
--kind
resonator kind (default lambda4)one of lambda4, lambda2
--finger-count N
lambda2 NCap finger count (1 to 10)type int
--squid-lj1-nh X
SQUID junction 1 inductance, nHtype float (finite)
--squid-lj2-nh X
SQUID junction 2 inductance, nHtype float (finite)
--flux-bias-phi0 X
flux bias, Phi0 (-1 to 1; default 0)type float (finite)
--flux-noise-uphi0 X
1/f flux-noise amplitude at 1 Hz, uPhi0/sqrt(Hz); given, a first-order dephasing estimate is addedtype float (finite)
--flux-noise-f-ir-hz X
infrared cut-off, Hz (default 1)type float (finite)
--flux-noise-t-us X
dephasing time scale, us (default 10)type float (finite)
--body JSON|PATH
base request: a JSON object or a .json file; flags override its fields
--fieldrequired
one of cross_length_um, claw_length_um, ground_spacing_um, junction_lj_nh, length_um, coupling_length_um
--startrequired
type float (finite)
--stoprequired
type float (finite)
--n
points (default 21; at most 201, or 41 per axis for two)type int
--field2
one of cross_length_um, claw_length_um, ground_spacing_um, junction_lj_nh, length_um, coupling_length_um
--start2
type float (finite)
--stop2
type float (finite)
--n2
type int
--json
print the exact API body as JSONflag
example
fluxus qubit sweep --cross-length-um 240 --claw-length-um 215 --length-um 3900 --field junction_lj_nh --start 8 --stop 14 --n 13
Same answer asPOST/v1/fluxus/qem/cross/sweep

fluxus qubit flux-sweep

tuning curve of a flux-tunable (SQUID) cell

The /api/qem/cross chain on a grid of flux points (/api/qem/cross/flux-sweep). Needs the SQUID: --squid-lj1-nh and --squid-lj2-nh, or a squid object in --body. EC, fr and kappa do not change with flux. No intervals.

usage
fluxus qubit flux-sweep [-h] [--cross-length-um X] [--claw-length-um X] [--ground-spacing-um X] [--junction-lj-nh X] [--cross-gap-um X] [--cross-width-um X] [--claw-width-um X] [--claw-gap-um X] [--length-um X] [--coupling-length-um X] [--center-width-um X] [--gap-um X] [--eps-r X] [--claw-cpw-length-um X] [--finger-length-um X] [--cap-gap-um X] [--cap-width-um X] [--kind {lambda4,lambda2}] [--finger-count N] [--squid-lj1-nh X] [--squid-lj2-nh X] [--flux-bias-phi0 X] [--flux-noise-uphi0 X] [--flux-noise-f-ir-hz X] [--flux-noise-t-us X] [--body JSON|PATH] [--n-points N_POINTS] [--flux-min-phi0 FLUX_MIN_PHI0] [--flux-max-phi0 FLUX_MAX_PHI0] [--json]

Arguments

--cross-length-um X
cross arm length, um (swept 90 to 420)type float (finite)
--claw-length-um X
claw length, um (swept 70 to 400; at most cross - 20)type float (finite)
--ground-spacing-um X
claw ground spacing, um (4.1 to 5.0 or 9.1 to 10.0)type float (finite)
--junction-lj-nh X
Josephson inductance, nH (free; sets EJ)type float (finite)
--cross-gap-um X
pinned at 30.0 by the HFSS configtype float (finite)
--cross-width-um X
pinned at 30.0type float (finite)
--claw-width-um X
pinned at 15.0type float (finite)
--claw-gap-um X
pinned at 5.1type float (finite)
--length-um X
resonator length, um (lambda4 2700 to 4700)type float (finite)
--coupling-length-um X
readout coupler length, um (lambda4 100 to 500)type float (finite)
--center-width-um X
CPW centre width, um (trained value 11.7)type float (finite)
--gap-um X
CPW gap, um (trained value 5.1)type float (finite)
--eps-r X
substrate permittivity (pinned at 11.45)type float (finite)
--claw-cpw-length-um X
claw stub, um (default 40, every HFSS row; another value is answered and flagged)type float (finite)
--finger-length-um X
lambda2 NCap finger length, um (15.9 to 60.9)type float (finite)
--cap-gap-um X
lambda2 NCap finger gap, um (1.1 to 6.1)type float (finite)
--cap-width-um X
lambda2 NCap finger width, um (4.9 to 14.9)type float (finite)
--kind
resonator kind (default lambda4)one of lambda4, lambda2
--finger-count N
lambda2 NCap finger count (1 to 10)type int
--squid-lj1-nh X
SQUID junction 1 inductance, nHtype float (finite)
--squid-lj2-nh X
SQUID junction 2 inductance, nHtype float (finite)
--flux-bias-phi0 X
flux bias, Phi0 (-1 to 1; default 0)type float (finite)
--flux-noise-uphi0 X
1/f flux-noise amplitude at 1 Hz, uPhi0/sqrt(Hz); given, a first-order dephasing estimate is addedtype float (finite)
--flux-noise-f-ir-hz X
infrared cut-off, Hz (default 1)type float (finite)
--flux-noise-t-us X
dephasing time scale, us (default 10)type float (finite)
--body JSON|PATH
base request: a JSON object or a .json file; flags override its fields
--n-points
flux points (2 to 101, default 41)type int
--flux-min-phi0
first flux point, Phi0 (default -0.5)type float (finite)
--flux-max-phi0
last flux point, Phi0 (default 0.5)type float (finite)
--json
print the exact API body as JSONflag
example
fluxus qubit flux-sweep --cross-length-um 240 --claw-length-um 215 --ground-spacing-um 10 --length-um 3900 --coupling-length-um 225 --squid-lj1-nh 14.53 --squid-lj2-nh 29.06 --n-points 61
Same answer asPOST/v1/fluxus/qem/cross/flux-sweep

fluxus qubit triage

accept / reject / simulate candidates

usage
fluxus qubit triage [-h] --require TARGET=LO:HI [--alpha ALPHA] [--json] file

Arguments

FILE
candidates: .jsonl, .json or .csv
--require TARGET=LO:HIrequired
repeatable
--alpha
type float (finite)
--json
print the exact API body as JSONflag
example
fluxus qubit triage cands.jsonl --require f01_ghz=4.3:4.7 --require anharmonicity_mhz=:-150
Same answer asPOST/v1/fluxus/qem/triage

fluxus qubit pad

Hamiltonian for a parallel-pad cell

usage
fluxus qubit pad [-h] [--pad-width-um X] [--pad-height-um X] [--pad-gap-um X] [--ground-gap-um X] [--junction-lj-nh X] [--length-um X] [--center-width-um X] [--gap-um X] [--eps-r X] [--coupling-cap-ff X] [--kind {lambda4,lambda2}] [--body JSON|PATH] [--engine {surrogate,oracle}] [--alpha ALPHA] [--json]

Arguments

--pad-width-um X
pad width, um (default 400)type float (finite)
--pad-height-um X
pad height, um (default 80)type float (finite)
--pad-gap-um X
gap between the pads, um (default 30)type float (finite)
--ground-gap-um X
pad edge to ground, um (default 30)type float (finite)
--junction-lj-nh, --lj-nh X
Josephson inductance, nH (default 12)type float (finite)
--length-um X
resonator length, um (default 4000)type float (finite)
--center-width-um X
CPW centre width, um (pinned at 10)type float (finite)
--gap-um X
CPW gap, um (pinned at 6)type float (finite)
--eps-r X
substrate permittivity (pinned at 11.45)type float (finite)
--coupling-cap-ff X
coupling capacitance, fF (default 5)type float (finite)
--kind
resonator kind (lambda2: the surrogate abstains)one of lambda4, lambda2
--body JSON|PATH
base request: a JSON object or a .json file; flags override its fields
--engine
one of surrogate, oracle
--alpha
type float (finite)
--json
print the exact API body as JSONflag
example
fluxus qubit pad --lj-nh 12 --length-um 4500
Same answer asPOST/v1/fluxus/qem

fluxus qubit verify

parallel-pad prediction against the oracle

usage
fluxus qubit verify [-h] [--pad-width-um X] [--pad-height-um X] [--pad-gap-um X] [--ground-gap-um X] [--junction-lj-nh X] [--length-um X] [--center-width-um X] [--gap-um X] [--eps-r X] [--coupling-cap-ff X] [--kind {lambda4,lambda2}] [--body JSON|PATH] [--engine {surrogate,oracle}] [--alpha ALPHA] [--json]

Arguments

--pad-width-um X
pad width, um (default 400)type float (finite)
--pad-height-um X
pad height, um (default 80)type float (finite)
--pad-gap-um X
gap between the pads, um (default 30)type float (finite)
--ground-gap-um X
pad edge to ground, um (default 30)type float (finite)
--junction-lj-nh, --lj-nh X
Josephson inductance, nH (default 12)type float (finite)
--length-um X
resonator length, um (default 4000)type float (finite)
--center-width-um X
CPW centre width, um (pinned at 10)type float (finite)
--gap-um X
CPW gap, um (pinned at 6)type float (finite)
--eps-r X
substrate permittivity (pinned at 11.45)type float (finite)
--coupling-cap-ff X
coupling capacitance, fF (default 5)type float (finite)
--kind
resonator kind (lambda2: the surrogate abstains)one of lambda4, lambda2
--body JSON|PATH
base request: a JSON object or a .json file; flags override its fields
--engine
one of surrogate, oracle
--alpha
type float (finite)
--json
print the exact API body as JSONflag
example
fluxus qubit verify --lj-nh 12 --length-um 4500
Same answer asPOST/v1/fluxus/qem/verify

fluxus qubit inverse

targets -> ranked TransmonCross designs

usage
fluxus qubit inverse [-h] [--f01-ghz F01_GHZ] [--anharmonicity-mhz ANHARMONICITY_MHZ] [--fr-ghz FR_GHZ] [--g-mhz G_MHZ] [--chi-mhz CHI_MHZ] [--weight TARGET=W] [--top TOP] [--n-geom N_GEOM] [--n-lj N_LJ] [--n-res N_RES] [--no-refine] [--body JSON|PATH] [--json]

Arguments

--f01-ghz
type float (finite)
--anharmonicity-mhz
type float (finite)
--fr-ghz
type float (finite)
--g-mhz
type float (finite)
--chi-mhz
type float (finite)
--weight TARGET=W
repeatable
--top
designs returned (1 to 20, default 3)type int
--n-geom
geometry grid (8 to 64, default 24)type int
--n-lj
junction grid (4 to 32, default 12)type int
--n-res
resonator grid (4 to 32, default 12)type int
--no-refine
flag
--body JSON|PATH
base request: a JSON object or a .json file; flags override its fields
--json
print the exact API body as JSONflag
example
fluxus qubit inverse --f01-ghz 4.5 --anharmonicity-mhz -200 --fr-ghz 6.5
Same answer asPOST/v1/fluxus/inv/cross

fluxus qubit inverse-pad

targets -> ranked parallel-pad cells

usage
fluxus qubit inverse-pad [-h] [--target NAME=VALUE] [--tolerance NAME=VALUE] [--n-candidates N_CANDIDATES] [--seed SEED] [--n-screen N_SCREEN] [--body JSON|PATH] [--json]

Arguments

--target NAME=VALUE
repeatable
--tolerance NAME=VALUE
repeatable
--n-candidates
type int
--seed
type int
--n-screen
type int
--body JSON|PATH
base request: a JSON object or a .json file; flags override its fields
--json
print the exact API body as JSONflag
example
fluxus qubit inverse-pad --target f01_ghz=4.8 --seed 1
Same answer asPOST/v1/fluxus/inv

fluxus qubit resonator

readout resonator fr (HFSS-trained)

usage
fluxus qubit resonator [-h] [--length-um LENGTH_UM] [--center-width-um CENTER_WIDTH_UM] [--gap-um GAP_UM] [--claw-length-um CLAW_LENGTH_UM] [--coupling-length-um COUPLING_LENGTH_UM] [--finger-length-um FINGER_LENGTH_UM] [--cap-gap-um CAP_GAP_UM] [--cap-width-um CAP_WIDTH_UM] [--ground-spacing-um GROUND_SPACING_UM] [--finger-count FINGER_COUNT] [--kind {lambda4,lambda2}] [--body JSON|PATH] [--json]

Arguments

--length-um
type float (finite)
--center-width-um
type float (finite)
--gap-um
type float (finite)
--claw-length-um
type float (finite)
--coupling-length-um
type float (finite)
--finger-length-um
type float (finite)
--cap-gap-um
type float (finite)
--cap-width-um
type float (finite)
--ground-spacing-um
type float (finite)
--finger-count
lambda2 NCap finger count; any NCap field selects the half-wave NCap engine (fr and kappa)type int
--kind
one of lambda4, lambda2
--body JSON|PATH
base request: a JSON object or a .json file; flags override its fields
--json
print the exact API body as JSONflag
example
fluxus qubit resonator --length-um 3900 --claw-length-um 215 --coupling-length-um 225
Same answer asPOST/v1/fluxus/resonator

fluxus qubit junction

Lj, Ic, EJ, Rn and area from one of them

usage
fluxus qubit junction [-h] [--lj-nh LJ_NH] [--ic-na IC_NA] [--ej-ghz EJ_GHZ] [--rn-ohm-room RN_OHM_ROOM] [--jc-ua-per-um2 JC_UA_PER_UM2] [--jc-a-per-cm2 JC_A_PER_CM2] [--tc-k TC_K] [--room-over-cold-ratio ROOM_OVER_COLD_RATIO] [--body JSON|PATH] [--json]

Arguments

--lj-nh
type float (finite)
--ic-na
type float (finite)
--ej-ghz
type float (finite)
--rn-ohm-room
type float (finite)
--jc-ua-per-um2
type float (finite)
--jc-a-per-cm2
type float (finite)
--tc-k
type float (finite)
--room-over-cold-ratio
type float (finite)
--body JSON|PATH
base request: a JSON object or a .json file; flags override its fields
--json
print the exact API body as JSONflag
example
fluxus qubit junction --lj-nh 10.76 --jc-ua-per-um2 0.5
Same answer asPOST/v1/fluxus/junction

fluxus qubit gds

TransmonCross qubit cell as a .gds file

usage
fluxus qubit gds [-h] [--cross-length-um X] [--claw-length-um X] [--ground-spacing-um X] [--junction-lj-nh X] [--cross-gap-um X] [--cross-width-um X] [--claw-width-um X] [--claw-gap-um X] [--length-um X] [--coupling-length-um X] [--center-width-um X] [--gap-um X] [--eps-r X] [--claw-cpw-length-um X] [--finger-length-um X] [--cap-gap-um X] [--cap-width-um X] [--kind {lambda4,lambda2}] [--finger-count N] [--squid-lj1-nh X] [--squid-lj2-nh X] [--flux-bias-phi0 X] [--flux-noise-uphi0 X] [--flux-noise-f-ir-hz X] [--flux-noise-t-us X] [--body JSON|PATH] [-o PATH] [--filename FILENAME] [--json]

Arguments

--cross-length-um X
cross arm length, um (swept 90 to 420)type float (finite)
--claw-length-um X
claw length, um (swept 70 to 400; at most cross - 20)type float (finite)
--ground-spacing-um X
claw ground spacing, um (4.1 to 5.0 or 9.1 to 10.0)type float (finite)
--junction-lj-nh X
Josephson inductance, nH (free; sets EJ)type float (finite)
--cross-gap-um X
pinned at 30.0 by the HFSS configtype float (finite)
--cross-width-um X
pinned at 30.0type float (finite)
--claw-width-um X
pinned at 15.0type float (finite)
--claw-gap-um X
pinned at 5.1type float (finite)
--length-um X
resonator length, um (lambda4 2700 to 4700)type float (finite)
--coupling-length-um X
readout coupler length, um (lambda4 100 to 500)type float (finite)
--center-width-um X
CPW centre width, um (trained value 11.7)type float (finite)
--gap-um X
CPW gap, um (trained value 5.1)type float (finite)
--eps-r X
substrate permittivity (pinned at 11.45)type float (finite)
--claw-cpw-length-um X
claw stub, um (default 40, every HFSS row; another value is answered and flagged)type float (finite)
--finger-length-um X
lambda2 NCap finger length, um (15.9 to 60.9)type float (finite)
--cap-gap-um X
lambda2 NCap finger gap, um (1.1 to 6.1)type float (finite)
--cap-width-um X
lambda2 NCap finger width, um (4.9 to 14.9)type float (finite)
--kind
resonator kind (default lambda4)one of lambda4, lambda2
--finger-count N
lambda2 NCap finger count (1 to 10)type int
--squid-lj1-nh X
SQUID junction 1 inductance, nHtype float (finite)
--squid-lj2-nh X
SQUID junction 2 inductance, nHtype float (finite)
--flux-bias-phi0 X
flux bias, Phi0 (-1 to 1; default 0)type float (finite)
--flux-noise-uphi0 X
1/f flux-noise amplitude at 1 Hz, uPhi0/sqrt(Hz); given, a first-order dephasing estimate is addedtype float (finite)
--flux-noise-f-ir-hz X
infrared cut-off, Hz (default 1)type float (finite)
--flux-noise-t-us X
dephasing time scale, us (default 10)type float (finite)
--body JSON|PATH
base request: a JSON object or a .json file; flags override its fields
-o, --output PATH
--filename
--json
print the exact API body as JSONflag
example
fluxus qubit gds --cross-length-um 240 --claw-length-um 215 -o q1.gds
Same answer asPOST/v1/fluxus/gds/cross

fluxus qubit gds-pad

parallel-pad cell + resonator as .gds

usage
fluxus qubit gds-pad [-h] [--pad-width-um X] [--pad-height-um X] [--pad-gap-um X] [--ground-gap-um X] [--junction-lj-nh X] [--length-um X] [--center-width-um X] [--gap-um X] [--eps-r X] [--coupling-cap-ff X] [--kind {lambda4,lambda2}] [--body JSON|PATH] [-o PATH] [--filename FILENAME] [--json]

Arguments

--pad-width-um X
pad width, um (default 400)type float (finite)
--pad-height-um X
pad height, um (default 80)type float (finite)
--pad-gap-um X
gap between the pads, um (default 30)type float (finite)
--ground-gap-um X
pad edge to ground, um (default 30)type float (finite)
--junction-lj-nh, --lj-nh X
Josephson inductance, nH (default 12)type float (finite)
--length-um X
resonator length, um (default 4000)type float (finite)
--center-width-um X
CPW centre width, um (pinned at 10)type float (finite)
--gap-um X
CPW gap, um (pinned at 6)type float (finite)
--eps-r X
substrate permittivity (pinned at 11.45)type float (finite)
--coupling-cap-ff X
coupling capacitance, fF (default 5)type float (finite)
--kind
resonator kind (lambda2: the surrogate abstains)one of lambda4, lambda2
--body JSON|PATH
base request: a JSON object or a .json file; flags override its fields
-o, --output PATH
--filename
--json
print the exact API body as JSONflag
example
fluxus qubit gds-pad -o cell.gds
Same answer asPOST/v1/fluxus/gds

fluxus qubit inductance

partial-inductance field solve

usage
fluxus qubit inductance [-h] [--segment x0,y0,z0,x1,y1,z1[,w][,t]] [--london-nm LONDON_NM] [--ground-plane-z-um GROUND_PLANE_Z_UM] [--body JSON|PATH] [--json]

Arguments

--segment x0,y0,z0,x1,y1,z1[,w][,t]
repeatable
--london-nm
type float (finite)
--ground-plane-z-um
type float (finite)
--body JSON|PATH
base request: a JSON object or a .json file; flags override its fields
--json
print the exact API body as JSONflag
example
fluxus qubit inductance --segment 0,0,0,100,0,0,2,0.1
Same answer asPOST/v1/fluxus/em/inductance

fluxus qubit yield

frequency-collision yield on a lattice

usage
fluxus qubit yield [-h] [--n-qubits N_QUBITS] [--lattice {heavy_hex,square}] [--target-f-ghz F1,F2,...] [--sigma-f-mhz SIGMA_F_MHZ] [--anharm-mhz ANHARM_MHZ] [--n-trials N_TRIALS] [--seed SEED] [--body JSON|PATH] [--json] [--detail]

Arguments

--n-qubits
qubits on the chip (required, here or in --body)type int
--lattice
one of heavy_hex, square
--target-f-ghz F1,F2,...
--sigma-f-mhz
type float (finite)
--anharm-mhz
type float (finite)
--n-trials
type int
--seed
type int
--body JSON|PATH
base request: a JSON object or a .json file; flags override its fields
--json
print the exact API body as JSONflag
--detail
per-qubit collision rates (/api/yld/detail)flag
example
fluxus qubit yield --n-qubits 127 --sigma-f-mhz 12 --seed 1
Same answer asPOST/v1/fluxus/yldPOST/v1/fluxus/yld/detail

fluxus qubit yield-curve

yield against frequency spread

usage
fluxus qubit yield-curve [-h] [--n-qubits N_QUBITS] [--lattice {heavy_hex,square}] [--target-f-ghz F1,F2,...] [--sigma-f-mhz SIGMA_F_MHZ] [--anharm-mhz ANHARM_MHZ] [--n-trials N_TRIALS] [--seed SEED] [--body JSON|PATH] [--json] [--sigmas S1,S2,...]

Arguments

--n-qubits
qubits on the chip (required, here or in --body)type int
--lattice
one of heavy_hex, square
--target-f-ghz F1,F2,...
--sigma-f-mhz
type float (finite)
--anharm-mhz
type float (finite)
--n-trials
type int
--seed
type int
--body JSON|PATH
base request: a JSON object or a .json file; flags override its fields
--json
print the exact API body as JSONflag
--sigmas S1,S2,...
example
fluxus qubit yield-curve --n-qubits 27 --sigmas 0,5,10,15 --seed 1
Same answer asPOST/v1/fluxus/yld/curve

fluxus qubit yield-graph

yield over your own graph

usage
fluxus qubit yield-graph [-h] [--sigma-f-mhz SIGMA_F_MHZ] [--anharm-mhz ANHARM_MHZ] [--n-trials N_TRIALS] [--seed SEED] [--body JSON|PATH] [--json] [file]

Arguments

FILE
.json with frequencies_ghz and edges
--sigma-f-mhz
type float (finite)
--anharm-mhz
type float (finite)
--n-trials
type int
--seed
type int
--body JSON|PATH
base request: a JSON object or a .json file; flags override its fields
--json
print the exact API body as JSONflag
example
fluxus qubit yield-graph chip.json --seed 1
Same answer asPOST/v1/fluxus/yld/graph

fluxus qubit chip

lattice map with default frequencies

usage
fluxus qubit chip [-h] [--n-qubits N_QUBITS] [--lattice {heavy_hex,square}] [--json]

Arguments

--n-qubits
type int · default 127
--lattice
one of heavy_hex, square · default heavy_hex
--json
print the exact API body as JSONflag
example
fluxus qubit chip --n-qubits 27
Same answer asGET/v1/fluxus/chip

fluxus qubit cell-eval

score one floorplan cell

usage
fluxus qubit cell-eval [-h] [--kind {quantum,sfq}] [--name NAME] [--param NAME=VALUE] [--body JSON|PATH] [--json]

Arguments

--kind
one of quantum, sfq · default quantum
--name
default transmon
--param NAME=VALUE
repeatable
--body JSON|PATH
base request: a JSON object or a .json file; flags override its fields
--json
print the exact API body as JSONflag
example
fluxus qubit cell-eval --name transmon
Same answer asPOST/v1/fluxus/cell/eval

fluxus qubit floorplan

evaluate a placed floorplan (.json)

usage
fluxus qubit floorplan [-h] [--body JSON|PATH] [--json] file

Arguments

FILE
.json with cells and wires
--body JSON|PATH
base request: a JSON object or a .json file; flags override its fields
--json
print the exact API body as JSONflag
example
fluxus qubit floorplan plan.json
Same answer asPOST/v1/fluxus/floorplan/eval

fluxus qubit preflight

logical-qubit preflight

usage
fluxus qubit preflight [-h] [--architecture ARCHITECTURE] [--n-qubits N_QUBITS] [--t1-us T1_US] [--t2-echo-us T2_ECHO_US] [--t-cz-ns T_CZ_NS] [--code-family {surface,repetition}] [--target-distance TARGET_DISTANCE] [--has-lru | --no-lru] [--body JSON|PATH] [--json]

Arguments

--architecture
--n-qubits
type int
--t1-us
type float (finite)
--t2-echo-us
type float (finite)
--t-cz-ns
type float (finite)
--code-family
one of surface, repetition
--target-distance
type int
--has-lru
flag
--no-lru
--body JSON|PATH
base request: a JSON object or a .json file; flags override its fields
--json
print the exact API body as JSONflag

Not together: has_lru / has_lru.

example
fluxus qubit preflight --has-lru --code-family surface
Same answer asPOST/v1/fluxus/preflight

fluxus qubit couple

two transmons: J, static ZZ, dressed levels

POST /api/coupling/pair. A LUMPED circuit: the capacitances are your inputs (Fluxus has no layout-to-capacitance model for multi-qubit chips). Capacitor between the qubits by default; --bus for a shared resonator. --from-cross fills both qubits from a TransmonCross answer as the studio's prefill does.

usage
fluxus qubit couple [-h] [--c1-ff X] [--c2-ff X] [--cc-ff X] [--q1-lj-nh X] [--q1-ej-ghz X] [--q1-f01-ghz X] [--q2-lj-nh X] [--q2-ej-ghz X] [--q2-f01-ghz X] [--levels LEVELS] [--from-cross JSON|PATH] [--bus] [--f1-ghz X] [--f2-ghz X] [--alpha1-mhz X] [--alpha2-mhz X] [--fr-ghz X] [--g1-mhz X] [--g2-mhz X] [--body JSON|PATH] [--json]

Arguments

--c1-ff X
qubit 1 capacitance to ground (shunt plus junction), fFtype float (finite)
--c2-ff X
qubit 2 capacitance to ground, fFtype float (finite)
--cc-ff X
capacitance between the qubits, fFtype float (finite)
--q1-lj-nh X
Josephson inductance, nHtype float (finite)
--q1-ej-ghz X
EJ / h, GHztype float (finite)
--q1-f01-ghz X
target BARE f01, GHz (EJ solved exactly)type float (finite)
--q2-lj-nh X
Josephson inductance, nHtype float (finite)
--q2-ej-ghz X
EJ / h, GHztype float (finite)
--q2-f01-ghz X
target BARE f01, GHz (EJ solved exactly)type float (finite)
--levels
levels per transmon (3 to 30)type int
--from-cross JSON|PATH
a /api/qem/cross body: C = e^2/(2h EC) of its answer (to 0.01 fF, as the studio prefill) and its junction (Lj, or EJ at the SQUID bias) for both qubits; flags override
--bus
use the bus model (implied by any bus flag)flag
--f1-ghz X
qubit 1 f01, GHztype float (finite)
--f2-ghz X
qubit 2 f01, GHztype float (finite)
--alpha1-mhz X
qubit 1 anharmonicity, MHz (negative)type float (finite)
--alpha2-mhz X
qubit 2 anharmonicity, MHz (negative)type float (finite)
--fr-ghz X
bus frequency, GHztype float (finite)
--g1-mhz X
qubit 1 to bus, MHztype float (finite)
--g2-mhz X
qubit 2 to bus, MHztype float (finite)
--body JSON|PATH
base request: a JSON object or a .json file; flags override its fields
--json
print the exact API body as JSONflag
example
fluxus qubit couple --from-cross q1.json --q2-lj-nh 10.6 --cc-ff 1
Same answer asPOST/v1/fluxus/coupling/pair

fluxus qubit coupler-sweep

tunable coupler: ZZ and coupling vs fc, idle points

POST /api/coupling/coupler-sweep: transmon, tunable coupler, transmon (Yan et al. 2018, Fig. 2(a)). Branch capacitances in fF, all your inputs.

usage
fluxus qubit coupler-sweep [-h] [--c1-ff X] [--c2-ff X] [--cc-ff X] [--c1c-ff X] [--c2c-ff X] [--c12-ff X] [--fc-min-ghz X] [--fc-max-ghz X] [--q1-lj-nh X] [--q1-ej-ghz X] [--q1-f01-ghz X] [--q2-lj-nh X] [--q2-ej-ghz X] [--q2-f01-ghz X] [--n-points N_POINTS] [--levels LEVELS] [--body JSON|PATH] [--json]

Arguments

--c1-ff X
qubit 1 to ground, fFtype float (finite)
--c2-ff X
qubit 2 to ground, fFtype float (finite)
--cc-ff X
coupler to ground, fFtype float (finite)
--c1c-ff X
qubit 1 to coupler, fFtype float (finite)
--c2c-ff X
qubit 2 to coupler, fFtype float (finite)
--c12-ff X
qubit 1 to qubit 2 (direct), fF; default 0type float (finite)
--fc-min-ghz X
coupler frequency from, GHztype float (finite)
--fc-max-ghz X
coupler frequency to, GHztype float (finite)
--q1-lj-nh X
Josephson inductance, nHtype float (finite)
--q1-ej-ghz X
EJ / h, GHztype float (finite)
--q1-f01-ghz X
target BARE f01, GHz (EJ solved exactly)type float (finite)
--q2-lj-nh X
Josephson inductance, nHtype float (finite)
--q2-ej-ghz X
EJ / h, GHztype float (finite)
--q2-f01-ghz X
target BARE f01, GHz (EJ solved exactly)type float (finite)
--n-points
points (2 to 81, default 41)type int
--levels
levels per transmon (3 to 8)type int
--body JSON|PATH
base request: a JSON object or a .json file; flags override its fields
--json
print the exact API body as JSONflag
example
fluxus qubit coupler-sweep --body docs/qubit/examples/yan2018_coupler.json
Same answer asPOST/v1/fluxus/coupling/coupler-sweep

fluxus qubit modes

any small lumped circuit: modes, anharmonicities, chi

POST /api/coupling/modes: exact diagonalisation of a capacitance matrix plus junctions (a trimon, a pair, a chain). Zero external flux, offset charge zero.

usage
fluxus qubit modes [-h] [--matrix ROWS|JSON|PATH] [--junction A,B,ej=X|lj=X] [--convention {branch,maxwell}] [--labels {normal,local}] [--levels LEVELS] [--body JSON|PATH] [--json]

Arguments

--matrix ROWS|JSON|PATH
capacitance matrix, fF: 'a,b;c,d' rows, JSON, or a .json file
--junction A,B,ej=X|lj=X
a junction from node A to node B (gnd for ground); repeat for eachrepeatable
--convention
one of branch, maxwell
--labels
one of normal, local
--levels
levels per mode (3 to 30)type int
--body JSON|PATH
base request: a JSON object or a .json file; flags override its fields
--json
print the exact API body as JSONflag
example
fluxus qubit modes --matrix "46,21,4,21;21,30,21,3;4,21,53,21;21,3,21,36" --junction 0,1,ej=8.16 --junction 1,2,ej=8.16 --junction 2,3,ej=8.16 --junction 3,0,ej=8.16
Same answer asPOST/v1/fluxus/coupling/modes

Generated from Fluxus 0.3.0 at commit b9aa57d on 2026-10-20 by python -m fluxus.docs_bundle.