qat.quops.is_trace_reducing

qat.quops.is_trace_reducing(quantum_channel: QuantumChannel, tol: float = 1e-08) → bool

Return True if the quantum channel is trace reducing within tolerance.

Parameters

• quantum_channel (QuantumChannel) – the quantum channel to check

• tol (float) – a tolerance

Returns

True if the channel is trace reducing.

Return type

bool

Notes

In the Kraus operator format, a channel is trace reducing if its Kraus operators \(E_k\) respects that \(\sum_k E_k^\dagger E_k\) has real eigenvalues between 0 and 1.