Europhys. Lett.
Volume 67, Number 6, September 2004
Page(s) 941 - 947
Section Electromagnetism, optics, acoustics, heat transfer, classical mechanics, and fluid dynamics
Published online 01 September 2004
Europhys. Lett., 67 (6), pp. 941-947 (2004)
DOI: 10.1209/epl/i2004-10144-3

Generation of nonclassical photon states using a superconducting qubit in a microcavity

Yu-xi Liu1, L. F. Wei1, 2 and Franco Nori1, 3

1  Frontier Research System, The Institute of Physical and Chemical Research (RIKEN) Wako-shi, Saitama, 351-0198, Japan
2  Institute of Quantum optics and Quantum information, Department of Physics Shanghai Jiaotong University - Shanghai 200030, PRC
3  Center for Theoretical Physics, Physics Department, CSCS The University of Michigan - Ann Arbor, MI 48109-1120, USA

(Received 13 April 2004; accepted in final form 8 July 2004)

Based on the interaction between the radiation field and a superconductor, we propose a way to engineer quantum states using a SQUID charge qubit inside a microcavity. This device can act as a deterministic single-photon source as well as generate any Fock states and an arbitrary superposition of Fock states for the cavity field. The controllable interaction between the cavity field and the qubit can be realized by the tunable gate voltage and classical magnetic field applied to the SQUID.

42.50.Dv - Nonclassical states of the electromagnetic field, including entangled photon states; quantum state engineering and measurements.
74.50.+r - Tunneling phenomena; point contacts, weak links, Josephson effects.
42.50.Ct - Quantum description of interaction of light and matter; related experiments.

© EDP Sciences 2004