Quantum purification spectroscopy

Bradraj Pandey (1) , Kirill Plekhanov (1, 2) , Guillaume Roux (1)

1 LPTMS - Laboratoire de Physique Théorique et Modèles Statistiques
2 CPHT - Centre de Physique Théorique [Palaiseau]

We discuss a protocol based on quenching a purified quantum system that allows one to capture bulk spectral features. It uses an infinite temperature initial state and an interferometric strategy to access the Loschmidt amplitude, from which the spectral features are retrieved via Fourier transform, providing coarse-grained approximation at finite times. It involves techniques available in current experimental setups for quantum simulation, at least for small systems. We illustrate possible applications in testing the eigenstate thermalization hypothesis and the physics of many-body localization.

Mots clés: Fundamental concepts

Domaines: Physique Générale [physics.gen-ph]

Bradraj Pandey, Kirill Plekhanov, Guillaume Roux. Quantum purification spectroscopy. Physical Review A, 2018, 98 (5), pp.050103. ⟨10.1103/PhysRevA.98.050103⟩. ⟨hal-01952908⟩