Analyzing the spectral density of a perturbed analog quantum simulator using Keldysh formalism

Autor: Zanker, Sebastian, Schwenk, Iris, Reiner, Jan-Michael, Leppäkangas, Juha, Marthaler, Michael
Rok vydání: 2017
Předmět:
Zdroj: Phys. Rev. B 97, 214301 (2018)
Druh dokumentu: Working Paper
DOI: 10.1103/PhysRevB.97.214301
Popis: Simulation of interacting electron systems is one of the great challenges of modern quantum chemistry and solid state physics. Controllable quantum systems offer the opportunity to create artificial structures which mimic the system of interest. An interesting quantity to extract from these quantum simulations is the spectral function. We map a noisy quantum simulator onto a fermionic system and investigate the influence of decoherence on the simulation of the spectral density using a diagrammatic approach on Keldysh contour. We show that features stronger than the single-qubit decoherence rate can be resolved, while weaker features wash out. For small systems, we compare our Keldysh approach to master-equation calculations.
Comment: 12 pages, 4 figures
Databáze: arXiv