Simulation de systèmes de matière condensée avec des ordinateurs quantiques. – (Lex Kemper / LPT / Seminar). – 5/09/2025, 11H

Séminaire LPT

Lex Kemper (Université d’État de Caroline du Nord)

Seminar LPT, 5/09/2025, 11H, 3R4, salle de conférence

Summary
In this talk, I’ll present our recent advances in using quantum computers to simulate condensed matter systems, focusing on spectroscopic experiments in and out of equilibrium.

First, I’ll introduce a linear response framework that directly connects experimental observables to quantum many-body states by computing bosonic and fermionic correlation functions on a quantum computer. Unlike prior methods, our approach supports multiple operators in a single circuit, enabling efficient and simultaneous extraction of various correlation functions without extra ancilla qubits. We demonstrate this on a charge-density-wave material using IBM’s ibm_auckland device, showing robust results even on noisy hardware. This method streamlines spectroscopic simulations and opens new directions for improving classical approaches.

Second, I’ll discuss simulating open quantum systems on noisy quantum hardware. We find that such systems are surprisingly robust to hardware errors—even with deep circuits—making them promising candidates for near-term simulations.

Together, this work demonstrates the feasibility and promise of quantum simulation for both equilibrium and non-equilibrium phenomena in complex materials.