Document type
Master thesisPublication date
Publication license
Please use this identifier to cite or link to this item: https://hdl.handle.net/2445/229308
Exploring the limits of many-body quantum metrology via adiabatic dynamics
Journal Title
Authors
Director/Tutor
Journal ISSN
Volume Title
Related resource
Abstract
The fundamental limits of thermal equilibrium (and ground state) metrology have been recently derived, thus providing an upper bound on the maximum precision we can extract when trying to estimate an unknown Hamiltonian parameter. Nevertheless, approaching and connecting these bounds with the dynamical Heisenberg limit still remains an open challenge. In this thesis, we first show how to approach the equilibrium bound via control on two-body interactions, and then we build an explicit connection between this result and the dynamical bound. In particular, we consider adiabatic protocols on the controllable part of the Hamiltonian, which make the system follow the ground state of the Hamiltonian throughout the evolution. If we impose adiabaticity locally, we manage to saturate both the Heisenberg and ground state metrology bounds in some particular models. We first exemplify these insights with a spin-squeezing Hamiltonian, and then we relate them to a paradigmatic model in condensed matter: the Heisenberg XXZ chain.
Description
Màster Oficial de Ciència i Tecnologia Quàntiques / Quantum Science and Technology, Facultat de Física, Universitat de Barcelona. Curs: 2024-2025. Tutors: Martí Perarnau-Llobet, John Calsamiglia Costa
Subject (English)
Citation
Citation
LUSZCZAK ANDRÉ, Erik. Exploring the limits of many-body quantum metrology via adiabatic dynamics. [consulted: 12 of June of 2026]. Available at: https://hdl.handle.net/2445/229308