Quantum Simulation of the Non-Fermi-Liquid State of Sachdev-Ye-Kitaev Model

TL;DR

This paper demonstrates the first nuclear-spin-chain quantum simulation of the SYK model, observing key phenomena like fermion pairing and chaos transition, advancing experimental studies of non-Fermi liquids and quantum chaos.

Contribution

It presents the initial experimental realization of the SYK model on a nuclear-spin-chain simulator, enabling exploration of its complex non-Fermi liquid physics.

Findings

Observed fermion pairing instability in the non-Fermi liquid state

Detected chaotic to non-chaotic transition at different temperatures

Validated theoretical predictions of SYK model behavior

Abstract

The Sachdev-Ye-Kitaev (SYK) model incorporates rich physics, ranging from exotic non-Fermi liquid states without quasiparticle excitations, to holographic duality and quantum chaos. However, its experimental realization remains a daunting challenge due to various unnatural ingredients of the SYK Hamiltonian such as its strong randomness and fully nonlocal fermion interaction. At present, constructing such a nonlocal Hamiltonian and exploring its dynamics is best through digital quantum simulation, where state-of-the-art techniques can already handle a moderate number of qubits. Here we demonstrate a first step towards simulation of the SYK model on a nuclear-spin-chain simulator. We observed the fermion paring instability of the non-Fermi liquid state and the chaotic-nonchaotic transition at simulated temperatures, as was predicted by previous theories. As the realization of the SYK model in practice, our experiment opens a new avenue towards investigating the key features of non-Fermi liquid states, as well as the quantum chaotic systems and the AdS/CFT duality.