Prethermalization and localization in quantum spin chains

How can a quantum many-body system escape the fate of thermalization is of importance to both fundamental study of quantum statistical physics and applications in quantum devices. Here we develop novel experimental and computational tools to address this question. First, novel control techniques are introduced to investigate prethermalization, a process where a quantum system fails to thermalize on a practical timescale. Prethermalization is demonstrated by measuring out-of-time ordered (OTO) correlations in nuclear spin systems with magnetic resonance techniques. Hamiltonian engineering enables tuning the strength of spin-spin interactions and of a transverse magnetic field in a spin chain system, as well as to invert the Hamiltonian sign to reveal OTO correlations. The experiments reveal that at high fields an emergent conserved quantity arises due to prethermalization, and the OTO commutator involving such prethermal conserved quantity saturates after a short time.

Name thesis:degree_name

Master

Department dc:contributor.department

Massachusetts Institute of Technology. Department of Electrical Engineering and Computer Science

Grantor dc:publisher

Massachusetts Institute of Technology

Year dc:date.issued

2019

Author dc:creator

• Peng, Pai(Scientist in electrical engineering and computer science)Massachusetts Institute of Technology.

Advisor dc:contributor.advisor

• Paola Cappellaro.

• Electrical Engineering and Computer Science.

Statement dc:rights

• MIT theses are protected by copyright. They may be viewed, downloaded, or printed from this source but further reproduction or distribution in any format is prohibited without written permission.

Licence dc:rights.uri

• http://dspace.mit.edu/handle/1721.1/7582

Language dc:language.iso

eng

Handle dc:identifier.uri

https://hdl.handle.net/1721.1/121659

OAI identifier oai:identifier

oai:dspace.mit.edu:1721.1/121659