Measurement optimization techniques for excited electronic states in near-term quantum computing algorithms

Understand

The variational quantum eigensolver (VQE) remains one of the most popular near-term quantum algorithms for solving the electronic structure problem.

• Yet, for its practicality, the main challenge to overcome is improving the quantum measurement efficiency.
• Numerous quantum measurement techniques have been developed recently, but it is unclear how these state-of-the-art measurement techniques will perform in extensions of VQE for obtaining excited electronic states.
• Assessing the measurement techniques' performance in the excited state VQE is crucial because the measurement requirements in these extensions are typically much greater than in conventional VQE, as one must measure the expectation value of multiple observables in addition to that of the electronic Hamiltonian.