scqubits.TunableTransmon.t1_effective#

TunableTransmon.t1_effective(noise_channels=None, common_noise_options=None, esys=None, get_rate=False, **kwargs)#

Calculate the effective \(T_1\) time (or rate).

The effective \(T_1\) is calculated by considering a variety of depolarizing noise channels, according to the formula:

\[\frac{1}{T_{1}^{\rm eff}} = \frac{1}{2} \sum_k \frac{1}{T_{1}^{k}}\]

where \(k\) runs over the channels that can contribute to the effective noise. By default all the depolarizing noise channels given by the method effective_noise_channels are included. Users can also provide specific noise channels, with selected options, to be included in the effective \(T_1\) calculation. For example, assuming qubit is a qubit object, can can execute:

tune_tmon.t1_effective(noise_channels=['t1_charge_impedance',
                        't1_flux_bias_line'],
                        common_noise_options=dict(T=0.050))
Parameters:

  • noise_channels (Union[str, List[str], List[Tuple[str, Dict]], None]) – channels to be plotted, if None then noise channels given by supported_noise_channels are used

  • common_noise_options (Optional[Dict]) – common options used when calculating coherence times

  • esys (Optional[Tuple[ndarray, ndarray]]) – spectral data used during noise calculations

  • get_rate (bool) – get rate or time

Return type:

float

Returns:

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

in inverse units.