quchip.utils.constants¶

Physical constants in the quchip GHz / ns / mK unit convention.

quchip does not use an hbar = 1 convention. Domain Hamiltonians express energies as E / h in ordinary (not angular) frequency, GHz; the single 2 * pi conversion to angular frequency happens later, at the engine assembly boundary. Times are expressed in ns and temperatures in mK.

Constants below are provided for user-facing physics expressions (thermal populations, flux quanta, etc.) and derived from SI defining values so the GHz/ns/mK-convention constants and their SI counterparts never drift apart.

All numerical values are taken from the CODATA 2018 recommended constants as published by NIST (https://physics.nist.gov/cuu/Constants/) and rescaled into the quchip unit system where applicable.

Module Attributes

`TWO_PI`	`2 * pi`.
`k_B`	Boltzmann constant in `GHz / mK`.
`hbar`	Reduced Planck constant in SI units, `J*s`.
`Phi_0`	Superconducting magnetic flux quantum `Phi_0 = h / (2 * e)` in Weber.

quchip.utils.constants.TWO_PI: float = 6.283185307179586¶: 2 * pi.

quchip.utils.constants.k_B: float = 0.020836619123327575¶

Boltzmann constant in GHz / mK.

Derived as k_B / h (both exact since the 2019 SI redefinition), rescaled from Hz/K to GHz/mK: approximately 2.0836619123e10 Hz/K, i.e. 2.0836619123e-2 GHz/mK.

quchip.utils.constants.hbar: float = 1.0545718176461565e-34¶

Reduced Planck constant in SI units, J*s.

Derived as h / (2 * pi) with h exact (CODATA 2018 / 2019 SI redefinition). quchip’s own Hamiltonians work in ordinary frequency, so this value is only needed when cross-checking against SI expressions.

quchip.utils.constants.Phi_0: float = 2.0678338484619295e-15¶

Superconducting magnetic flux quantum Phi_0 = h / (2 * e) in Weber.

Derived from h and e, both exact since the 2019 SI redefinition (CODATA 2018): approximately 2.067833848e-15 Wb.