Optimization of Simultaneous Measurement for Variational Quantum Eigensolver Applications

Autor: Margaret Martonosi, Olivia Angiuli, Kaiwen Gui, Yongshan Ding, Teague Tomesh, Martin Suchara, Pranav Gokhale, Frederic T. Chong
Rok vydání: 2020
Předmět:
Zdroj: QCE
Popis: Variational quantum eigensolver (VQE) is a promising algorithm suitable for near-term quantum computers. VQE aims to approximate solutions to exponentially-sized optimization problems by executing a polynomial number of quantum subproblems. However, the number of subproblems scales as N4 for typical problems of interest-a daunting growth rate that poses a serious limitation for emerging applications such as quantum computational chemistry. We mitigate this issue by exploiting the simultaneous measurability of subproblems corresponding to commuting terms. Our technique transpiles VQE instances into a format optimized for simultaneous measurement, ultimately yielding 8-30x lower cost. Our work also encompasses a synthesis tool for compiling simultaneous measurement circuits with minimal overhead. We demonstrate experimental validation of our techniques by estimating the ground state energy of deuteron with a quantum computer. We also investigate the underlying statistics of simultaneous measurement and devise an adaptive strategy for mitigating harmful covariance terms.
Databáze: OpenAIRE