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arXiv · 2401.15303

Feedback-based Quantum Algorithm Inspired by Counterdiabatic Driving

Rajesh K. Malla·Hiroki Sukeno·Hongye Yu·Tzu-Chieh Wei·Andreas Weichselbaum·Robert M. Konik
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Abstract

In recent quantum algorithmic developments, a feedback-based approach has shown promise for preparing quantum many-body system ground states and solving combinatorial optimization problems. This method utilizes quantum Lyapunov control to iteratively construct quantum circuits. Here, we propose a substantial enhancement by implementing a protocol that uses ideas from quantum Lyapunov control and the counterdiabatic driving protocol, a key concept from quantum adiabaticity. Our approach introduces an additional control field inspired by counterdiabatic driving. We apply our algorithm to prepare ground states in one-dimensional quantum Ising spin chains. Comprehensive simulations demonstrate a remarkable acceleration in population transfer to low-energy states within a significantly reduced time frame compared to conventional feedback-based quantum algorithms. This acceleration translates to a reduced quantum circuit depth, a critical metric for potential quantum computer implementation. We validate our algorithm on the IBM cloud computer, highlighting its efficacy in expediting quantum computations for many-body systems and combinatorial optimization problems.

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Rajesh K. Malla, Hiroki Sukeno, Hongye Yu, Tzu-Chieh Wei, Andreas Weichselbaum, Robert M. Konik. 2024-01-27. Feedback-based Quantum Algorithm Inspired by Counterdiabatic Driving. https://arxiv.org/abs/2401.15303

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