Department of Nuclear and Atomic Physics Seminars

Fast and coherent single-photon interface for fiber-integrated quantum memories

by Dr. Dr. Deepak Pandey (Institut fuer Angewandte Physik, Bonn, Germany)

Tuesday, November 20, 2018 from to (Asia/Kolkata)
at TIFR,Mumbai ( AG-69 )
Description
We are living at the intriguing crossroad of quantum and classical technology merger which
would allow to conceive fully scalable quantum systems capable of performing quantum
information and computational tasks. This however is feasible with the realization of
miniaturized and scalable quantum technologies.
In this talk I will present our efforts in working with a single atom-cavity system in the strong
coupling regime, particularly in fiber-based optical cavities. These microscopic cavities
which are carved directly on an optical fiber end facet, presents a miniaturized and scalable
quantum technology with far reaching implications. I will discuss the case of a single
rubidium atom strongly coupled to such a high-finesse cavity. This represents the
fundamental building block for a scalable quantum system in a bottoms up approach. Our
recent observations concerning the Purcell enhancement of the atomic emission into the
cavity mode will be discussed. These experimental findings have allowed us to use the
system for storing single photons in an atom-cavity system. We have stored photons with
temporal widths smaller than the excited state lifetime of the atom. This is crucial to realize
fast and fiber-network compatible quantum memories.
Finally, I will discuss future prospects on the generation of scalable multi-particle entangled
states in a cavity with potential applications in meteorology and precision experiments.
References:
1) Strong Purcell effect on a neutral atom trapped in an open fiber cavity, Phys. Rev. Lett. 2018.
2) Bose-Einstein condensate array in a malleable optical trap formed in a traveling wave cavity,
Quantum Science and Technology, 3, 045009 (2018).