Acceleration of probabilistic imaginary-time evolution method combined with quantum amplitude amplification

Understand

A probabilistic imaginary-time evolution (PITE) method was proposed as a nonvariational method to obtain a ground state on a quantum computer.

• In this formalism, the success probability of obtaining all imaginary-time evolution operators acting on the initial state decreases as the imaginary time proceeds.
• To alleviate the undesirable nature, we propose quantum circuits for PITE combined with the quantum amplitude amplification (QAA) method.
• We reduce the circuit depth in the combined circuit with QAA by introducing a pre-amplification operator.