Analog quantum simulation of chemical dynamics

TL;DR

This paper proposes an analog quantum simulation method for chemical dynamics that efficiently models molecular vibrations and complex reactions, surpassing classical computational limits and existing digital quantum approaches.

Contribution

It introduces a resource-efficient analog quantum simulation technique using bosonic modes, enabling realistic and scalable modeling of complex chemical reactions.

Findings

Simulates molecular vibrations with bosonic modes

Achieves higher time resolution than ultrafast spectroscopy

Can be implemented with current quantum technology

Abstract

Ultrafast chemical reactions are difficult to simulate because they involve entangled, many-body wavefunctions whose computational complexity grows rapidly with molecular size. In photochemistry, the breakdown of the Born-Oppenheimer approximation further complicates the problem by entangling nuclear and electronic degrees of freedom. Here, we show that analog quantum simulators can efficiently simulate molecular dynamics using commonly available bosonic modes to represent molecular vibrations. Our approach can be implemented in any device with a qudit controllably coupled to bosonic oscillators and with quantum hardware resources that scale linearly with molecular size, and offers significant resource savings compared to digital quantum simulation algorithms. Advantages of our approach include a time resolution orders of magnitude better than ultrafast spectroscopy, the ability to simulate large molecules with limited hardware using a Suzuki-Trotter expansion, and the ability to implement realistic system-bath interactions with only one additional interaction per mode. Our approach can be implemented with current technology; e.g., the conical intersection in pyrazine can be simulated using a single trapped ion. Therefore, we expect our method will enable classically intractable chemical dynamics simulations in the near term.