English

Quantum Simulation of Non-Hermitian Linear Response via Schr\"odingerization

Quantum Physics 2026-03-31 v2

Abstract

Linear response theory and Green's functions provide a universal framework for understanding dynamical correlations in strongly correlated open quantum systems. While the theoretical foundation for non-Hermitian linear response has been recently established to describe dissipation and fluctuation-dissipation relations (FDR), generalizing these predictions onto practical quantum computers remains a formidable algorithmic challenge due to the intrinsically non-unitary nature of the dynamics. In this work, we present a systematic algorithmic framework that seamlessly transforms non-unitary multi-time correlation functions into a unitary form viable for digital quantum hardware. By mapping the vectorization of the Lindblad master equation into an expanded continuous-variable Liouville space, we employ the Schr\"odingerization technique to deterministically evaluate the non-Hermitian response. Furthermore, through hardware-aware simulations utilizing a 133-qubit device noise model, we demonstrate that our unitary framework robustly preserves the fundamental spectral information -- specifically the phase and oscillatory frequency -- against realistic depolarizing channels. By bypassing explicit non-unitary mid-circuit measurements, this approach intrinsically supports the integration of standard quantum error mitigation protocols, providing a scalable algorithmic blueprint for probing open-system universality on near-term hardware.

Keywords

Cite

@article{arxiv.2603.17342,
  title  = {Quantum Simulation of Non-Hermitian Linear Response via Schr\"odingerization},
  author = {Jeongbin Jo},
  journal= {arXiv preprint arXiv:2603.17342},
  year   = {2026}
}

Comments

8 pages, update simulation results

R2 v1 2026-07-01T11:25:31.985Z