Many-body Effects in Atomic Ensembles Probed by Optical Two-dimensional Coherent Spectroscopy

Authors

Danfu LiangFollow

Document Type

Dissertation

Degree

Doctor of Philosophy (PhD)

Major/Program

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First Advisor's Name

Hebin Li

First Advisor's Committee Title

Committee chair

Second Advisor's Name

Yifu Zhu

Second Advisor's Committee Title

Committee member

Third Advisor's Name

Wim Cosyn

Third Advisor's Committee Title

Committee member

Fourth Advisor's Name

Francisco Alberto Fernandez Lima

Fourth Advisor's Committee Title

Committee member

Keywords

2D coherent spectroscopy, dipole-dipole interaction, cold atoms

Date of Defense

5-23-2022

Abstract

Quantum information science provides humankind with post-Moore era technology and advanced principles and methods in the development of information science. Implementing practical quantum simulations through many-body quantum systems is a fundamental goal in quantum information science. Therefore, the demand for the achievement of quantum information processing devices inevitably requires the study of the many-body effect in the multi-atom system. Due to the transition-induced dipole moment, neutral atoms can interact without a permanent dipole moment. The interaction plays an essential role in many-body effects, such as energy shifts and changes in dephasing rates. In addition, its long-range nature has confirmed the necessity of including the interactions in studying many-body systems.

My Ph.D. research focuses on interacting alkali-metal atomic ensembles to unveil the critical contributions of dipole-dipole interactions in many-body physics by using optical two-dimensional coherent spectroscopy (2DCS). This unique technique of optical 2DCS combined with modulated phases is extremely sensitive, allowing us to access the weak interaction and measure the energy shift and changes in dephasing rates.

First, I probed the dipole-dipole interactions induced by the higher excited state in double-quantum, making it possible to design a versatile platform to model a more complex Hamiltonian that can include different types of many-body interactions. Second, the scalable and deterministic many-body interaction and correlation of multi-atom have been detected via multi-quantum 2DCS. This work can contribute to the study of quantum information. Third, the sensitivity of 2DCS has been improved to the single-atom level. This work will lead to the realization of ultrafast nonlinear spectroscopy of single atoms. The measured single-atom characteristics will be crucial for explaining how individuals contribute to a system’s ensemble response. At last, I probed interatomic interactions and correlations in a cold atomic cloud. This work can benefit the study of cold atoms/molecules in the time domain and has potential applications in probing the chemical reaction dynamics of cold molecules.

Identifier

FIDC010716

Recommended Citation

Liang, Danfu, "Many-body Effects in Atomic Ensembles Probed by Optical Two-dimensional Coherent Spectroscopy" (2022). FIU Electronic Theses and Dissertations. 5082.
https://digitalcommons.fiu.edu/etd/5082