scqubits.Fluxonium.t1_quasiparticle_tunneling#

Fluxonium.t1_quasiparticle_tunneling(i=1, j=0, Y_qp=None, x_qp=3e-06, T=0.015, Delta=0.00034, total=True, esys=None, get_rate=False, noise_op=None)#

Noise due to quasiparticle tunneling across a Josephson junction.

References: Smith et al (2020), Catelani et al (2011), Pop et al (2014).

Parameters:

  • i (int >=0) – state index that along with j defines a transition (i->j)

  • j (int >=0) – state index that along with i defines a transition (i->j)

  • Y_qp (Union[float, Callable, None]) – complex admittance; a fixed value or function of omega

  • x_qp (float) – quasiparticle density (in units of eV)

  • T (float) – temperature in Kelvin

  • Delta (float) – superconducting gap (in units of eV)

  • total (bool) – if False return a time/rate associated with a transition from state i to state j. if True return a time/rate associated with both i to j and j to i transitions

  • esys (Optional[Tuple[ndarray, ndarray]]) – evals, evecs tuple

  • get_rate (bool) – get rate or time

  • noise_op (ndarray | csc_matrix | Qobj | None) –

Returns:

time or rate – decoherence time in units of \(2\pi ({\rm system\,\,units})\), or rate in inverse units.

Return type:

float