Hybrid digital-analog protocols for simulating quantum multi-body interactions

TL;DR

This paper introduces a hybrid digital-analog quantum protocol that enables the simulation of complex multi-body interactions, overcoming hardware limitations and demonstrating its effectiveness on a trapped-ion quantum processor.

Contribution

The paper presents a novel hybrid digital-analog method for simulating non-perturbative multi-body Hamiltonians with non-commuting terms, surpassing previous digital or analog approaches.

Findings

Successfully implemented on a trapped-ion processor

Realized a topological spin chain with prethermal zero modes

Simulated three- and four-body interactions effectively

Abstract

While quantum simulators promise to explore quantum many-body physics beyond classical computation, their capabilities are limited by the available native interactions in the hardware. On many platforms, accessible Hamiltonians are largely restricted to one- and two-body interactions, limiting access to multi-body Hamiltonians and to systems governed by simultaneous, non-commuting interaction terms that are central to condensed matter, quantum chemistry, and high-energy physics. We introduce and experimentally demonstrate a hybrid digital-analog protocol that overcomes these limitations by embedding analog evolution between shallow entangling-gate layers. This method produces effective Hamiltonians with simultaneous non-commuting three- and four-body interactions that are generated non-perturbatively and without Trotter error -- capabilities not practically attainable on near-term hardware using purely digital or purely analog schemes. We implement our scheme on a trapped-ion quantum processor and use it to realize a topological spin chain exhibiting prethermal strong zero modes persisting at high temperature, as well as models featuring three- and four-body interactions. Our hardware-agnostic and scalable method opens new routes to realizing complex many-body physics across quantum platforms.