How Variational quantum algorithms behave part1(Quantum Computing)
- Investigation of Perturbation Theory with Variational Quantum Algorithm(arXiv)
Author : H. Davoodi Yeganeh
Abstract : Variational Quantum Algorithms are among the most promising systems to implement quantum computing under the Noisy-Intermediate Scale Quantum (NISQ) technology. In variational quantum algorithm, wavefunction represented by a parametrized ansatz and variational parameters are updated iteratively with a classical computer based on the measurement outputs from the quantum computer. In this paper, we investigate perturbation theory with these algorithms and prospect the possibility of using the variational quantum algorithm to simulate quantum dynamics in perturbation theory. We illustrate the use of algorithms with detailed examples which are in good agreement with analytical calculations
2. PANSATZ: Pulse-based Ansatz for Variational Quantum Algorithms(arXiv)
Author : Dekel Meirom, Steven H. Frankel
Abstract : We develop and implement a novel pulse-based ansatz, which we call PANSATZ, for more efficient and accurate implementations of variational quantum algorithms (VQAs) on today’s noisy intermediate-scale quantum (NISQ) computers. Our approach is applied to quantum chemistry. Specifically, finding the ground-state energy associated with the electron configuration problem, using the variational quantum eigensolver (VQE) algorithm for several molecules. We manage to achieve chemical accuracy both in simulation for several molecules and on one of IBM’s NISQ devices for the H2 molecule in the STO-3G basis. Our results are compared to a gate-based ansatz and show significant latency reduction — up to 7× shorter ansatz schedules. We also show that this ansatz has structured adaptivity to the entanglement level required by the problem
