报告题目：Efficient coupling of Rydberg atoms to microwave fields: applications for microwave-to-optical conversion and imaging of ions
报告人：Thibault Vogt（新加坡国立大学量子科技中心高级研究员）
报告时间：2020年1月2日（星期四）下午4:30—5:30
报告地点：激光光谱研究所三层报告厅
报告简介：
The coupling of microwave or THz fields with Rydberg atoms is orders of magnitude larger than with ground state atoms. Microwave dressing of electromagnetically induced transparency involving a Rydberg state (Rydberg EIT) for the measurement of traceable microwave fields is one of the many applications of this large coupling that has been developed.
In a first part of this talk, I will discuss our recent demonstration of microwave-to-optical conversion using a near-resonant six-wave mixing scheme involving Rydberg energy levels in cold 87Rb atoms [1]. Interconversion between microwave and optical fields is going to be used in future quantum information networks for interfacing superconducting qubits and optical fibers. Finding a system that can achieve coherent, relatively efficient, and broadband conversion is essential prior to realizing any quantum state transfer between microwave and optical photons. Our experiment is performed with a free-space microwave field, and reaches a conversion efficiency of about 5% for the microwave photons entering the non-linear medium [2].
In the second part of my talk, I will discuss our recent implementation of the detection of ions embedded in an atomic gas using microwave-assisted Rydberg EIT [3]. The detection scheme relies on Rydberg EIT to the 27G state. The 27G state is very sensitive to the small electrostatic fields created by ions because of its large polarizability, and the resulting energy shifts can make Rydberg EIT become opaque. We demonstrate imaging of ions in an atomic gas using the induced absorption caused by this ion-Rydberg atom interaction [4].
[1] J. Han, T. Vogt, C. Gross, D. Jaksch, M. Kiffner, and W. Li, Phys. Rev. Lett. 120, 093201, 2018
[2] T. Vogt, C. Gross, J. Han, S. B. Pal, M. Lam, M. Kiffner, and W. Li, Phys. Rev. A 99, 23832, 2019
[3] T. Vogt, C. Gross, T. F. Gallagher, and W. Li, Opt. Lett., 43, 1822-1825, 2018
[4] C. Gross, T. Vogt, and W. Li , arXiv:1910.12040
报告人简介：
Thibault Vogt，男，新加坡国立大学量子科技中心高级研究员，2007年获法国巴黎第十一大学理学博士学位，2007年-2012年先后在美国弗吉尼亚大学，中国北京大学从事博士后研究工作。主要开展了里德堡原子多体物理, 量子模拟，量子信息等多体量子系统，强相互作用里德堡原子的激发动力学效应和里德堡分子，玻色-爱因斯坦凝聚等方面的研究工作。发表SCI检索论文30余篇，其中有《Physical Review Letters》、《Physical Review A》、《New J. Physics》、《Journal of Chemical Physics》、《Optics Letters》等顶尖杂志。论文内容涉及超冷里德堡原子分子物理，玻色-爱因斯坦凝聚和量子计算等物理学前沿科学问题的理论和实验研究。