How is the expectation value of an operator ( A ) in a quantum state described by ( ρ ) calculated, and why is this formulation important for VQE?
Tuesday, 11 June 2024
by EITCA Academy
The expectation value of an operator in a quantum state described by the density matrix is a fundamental concept in quantum mechanics, particularly relevant in the context of the Variational Quantum Eigensolver (VQE). To calculate this expectation value, the following procedure is employed: Given a quantum state and an observable , the expectation value is