# BaseStateFidelity¶

class BaseStateFidelity[source]

Bases: ABC

An interface to calculate state fidelities (state overlaps) for pairs of (parametrized) quantum circuits. The calculation depends on the particular fidelity method implementation, but can be always defined as the state overlap:

$|\langle\psi(x)|\phi(y)\rangle|^2$

where $$x$$ and $$y$$ are optional parametrizations of the states $$\psi$$ and $$\phi$$ prepared by the circuits circuit_1 and circuit_2, respectively.

Methods

 create_fidelity_circuit Implementation-dependent method to create a fidelity circuit from 2 circuit inputs. run Runs asynchronously the state overlap (fidelity) calculation between two (parametrized) circuits (first and second) for a specific set of parameter values (first and second).