Speaker
Prof.
Gentaro Watanabe
(Asia Pacific Center for Theoretical Physics (APCTP))
Description
Dissipation is typically considered to be a serious enemy to
quantum systems as it leads to a rapid decay of the
coherence. Surprisingly, however, recent studies show that
an appropriately designed coupling between the system and
the reservoir can drive the system into a given pure state
[1,2]. This opens the way for the use of dissipation in
quantum state engineering.
Here we present a method to create phase- and number-
squeezed states in two-mode Bose systems using
dissipation [3]. Creating squeezed states is a key issue in
interferometry as they allow the improvement of
precision measurements beyond the conventional bound
attainable by classical means. The effectiveness of this
method is demonstrated by considering cold Bose gases
trapped in a double-well potential. The extension of our
formalism to an optical lattice gives control of the phase
boundaries of the steady-state phase diagram, and we
discover a new phase characterized by a non-zero
condensate fraction and thermal-like particle number
statistics. We also propose a physical setup to realize our
sceme.
References
[1] S. Diehl et al., Nature Phys. 4, 878 (2008).
[2] B. Kraus et al., Phys. Rev. A 78, 042307 (2008).
[3] G. Watanabe and H. Mäkelä, Phys. Rev. A 85, 023604
(2012).
Primary author
Prof.
Gentaro Watanabe
(Asia Pacific Center for Theoretical Physics (APCTP))
