Transport and Localization in many-body nuclear spin systems

Event Dates: 

Wednesday, November 30, 2016 - 4:00pm

CTQM Seminar Type: 

  • Related Seminar Series

Speaker Name(s): 

Paola Cappellaro

Speaker Affiliation(s): 

Massachusetts Institute of Technology

Abstract, Event Details: 

A large-scale quantum computer could solve problems that would take classical computers longer than the age of the universe to crack, with profound implications for cryptography, chemistry, material science, and many areas of physics. However, to reach this goal we need to control large quantum systems, where the many-body dynamics becomes often fragile and very complex.
Among the many questions and challenges that arise when working toward this goal, I will address two questions in my talk: How can we transfer quantum information from one quantum register to another?
How can we preserve quantum information in the presence of strong interactions?
Using a nuclear spin chain as an exemplary experimental system, and the tools of Hamiltonian engineering, I will show how spin chains can act as quantum wires in a distributed quantum computing architecture, transporting information and entanglement. I will then show how disorder can quench the transport of information, a phenomenon known as localization. This phenomenon might actually be a feature in some situations, as it allows preserving local quantum information for later retrieval and prevents thermalization. Is localization however possible even in the presence of long-range interaction? I will show experimental signatures that a logarithmic growth of long-range correlation is still present in interacting systems, a sign of many-body localization.