Dynamics in a Fermi lattice gas

Xu, Wenchao

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https://hdl.handle.net/2142/100912 Copy

Description

Title

Dynamics in a Fermi lattice gas

Author(s)

Xu, Wenchao

Issue Date

2018-03-26

Director of Research (if dissertation) or Advisor (if thesis)

DeMarco, Brian

Doctoral Committee Chair(s)

Abbamonte, Peter

Committee Member(s)

• Ceperley, David
• Odom, Brian

Department of Study

Physics

Discipline

Physics

Degree Granting Institution

University of Illinois at Urbana-Champaign

Degree Name

Ph.D.

Degree Level

Dissertation

Keyword(s)

Dynamics, Fermi-Hubbard model

Abstract

We use 40K atoms trapped in a cubic optical lattice to simulate the Fermi-Hubbard model. The work in this thesis focuses on investigating dynamics in the Fermi-Hubbard model and developing techniques for engineering Hamiltonians beyond the minimal Hubbard model. We discussed three experiments. In the first, we investigated the transport properties of a Fermi lattice gas by directly measuring the transport lifetime at various interaction strengths and temperatures. The resistivity is inferred from the measured transport lifetime. We observe anomalous transport behavior, which is analogous to bad-metal behavior in strongly correlated electronic materials. The second experiment presents the first realization of correlated, density-dependent tunneling in a Fermi-Hubbard optical lattice model by applied Raman laser fields. This correlated tunneling involves spin-flips and the generation of doublons, which have been observed experimentally. We also confirmed that the amplitude of correlated tunneling is suppressed when neighboring lattice sites are unoccupied. The last experiment explores the possibility to introduce long-range interactions for fermions trapped in optical lattices via Rydberg-dressed states. We developed a novel velocity-selective spectroscopy method to measure the transition between the 5P_1/2 and Rydberg states via electromagnetically induced transparency. This measurement is a first step toward inducing Rydberg-dressed interactions in optical lattices.

Graduation Semester

2018-05

Type of Resource

text

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http://hdl.handle.net/2142/100912

Copyright and License Information

Copyright 2018 Wenchao Xu

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