Efficient multi-qubit gates for simulating chemical dynamics in trapped-ion quantum computers

Simulating the dynamics of quantum chemical systems is a promising application of quantum computers. While most quantum algorithms and experimental demonstrations have focused on calculations of electronic structure in molecules, a recently developed protocol [1] proposed techniques to simulate nuclear dynamics in a Hydrogen-bonded system and was recently demonstrated in a trapped-ion quantum computer [2]. Here we propose a more efficient decomposition of Hamiltonians which describe proton transfer in chemical systems using multi-qubit gates and single qubit rotations. Leveraging the all-to-all connectivity of global Molmer-Sorensen interactions in trapped-ion systems, we show an efficient decomposition into layers of global multi-qubit gates and local single qubit rotations. We present a thorough study of the experimental feasibility of our approach and comparison against more common universal gate sets available in generic quantum computers. Our proposal offers the potential to perform efficient simulation of quantum chemical dynamics on trapped-ion quantum simulators well into the regime of classical intractability.

[1] D. Saha et al, J. Chem. Theory Comput. 17, 6713 (2021)

[2] P. Richerme, et al., arXiv:2204.08571 (2022)