Title: [Joint CQSE & NCTS Seminar] Electromagnetically induced transparency in superconducting circuits controlled by a parametric drive
Speaker: Prof. Yung-Fu Chen (Department of Physics, National Central University)
Date: Apr. 29, 2022, 14:30-15:30
Place: Rm. 104, Chin-Pao Yang Lecture Hall, CCMS & New Physics Building, NTU
Online Link: https://nationaltaiwanuniversity-zbh.my.webex.com/nationaltaiwanuniversity-zbh.my/j.php?MTID=m3efd6c4a404b85f1e7a186a89d9b9009

Abstract:
Superconducting artificial atoms can strongly interact with itinerant photons
propagating in one-dimension transmission lines, forming the waveguide quantum
electrodynamics architecture. The architecture is proposed to establish a quantum
network to process quantum information. Electromagnetically induced transparency
(EIT) is a quantum interference effect occurred in three-level Λ-type atoms. The
absorption and dispersion of a probe light owing to the atoms is greatly modified by
another control light due to a destructive interference effect. The atoms become
transparent for the probe light, and the light can travel extremely slowly and even be
trapped by the atoms. This controlled interference effect can be utilized to build a
quantum memory, one of the fundamental components required for the quantum
network. However, the lack of long coherent metastable states in superconducting
artificial atoms poses a challenge to realize an EIT-based quantum memory. In this talk,
we introduce two superconducting quantum circuits to achieve EIT. The required
metastable state can be achieved by either the subradiance state of a coupled resonant
qubits or a high-quality resonator. We utilize ac parametric modulation of the atom
frequency to open up a transition to a suitable metastable state. The success of these Λ-type
EIT schemes will advance the developments of quantum memory in superconducting circuits.

Biography Brief:
Education
Ph.D. in Physics, University of Maryland, College Park (08/2000 – 04/2006)
B.S. in Physics, National Taiwan University (10/1994 – 06/1998)

Work Experience
Associate Professor
Department of Physics, National Central University (08/2017 – present)

Assistant Professor
Department of Physics, National Central University (08/2011 – 07/2017)

Postdoctoral Research Associate
Department of Physics, University of Wisconsin-Madison (05/2009 – 06/2011)

Postdoctoral Research Associate
Department of Physics and Materials Research Laboratory, University of Illinois at Urbana-Champaign (05/2006 – 05/2009)

Research Assistant
Department of Physics and Center for Superconductivity Research, University of Maryland, College Park (05/2001 – 04/2006)

Recent research focus
superconducting quantum circuits