3,228 research outputs found
Correlated two-photon transport in a one-dimensional waveguide side-coupled to a nonlinear cavity
We investigate the transport properties of two photons inside a
one-dimensional waveguide side-coupled to a single-mode nonlinear cavity. The
cavity is filled with a nonlinear Kerr medium. Based on the Laplace transform
method, we present analytic solution of quantum states of the transmitted and
reflected two photons, which are initially prepared in a Lorentzian wave
packet. The solution reveals how quantum correlation between the two photons
emerge after the scattering by the nonlinear cavity. In particular, we show
that the output wave function of the two photons in position space can be
localized in the relative coordinates, which is a feature that may be
interpreted as a two-photon bound state in this waveguide-cavity system.Comment: 9 pages, 5 figure
Parametric generation of quadrature squeezing of mirrors in cavity optomechanics
We propose a method to generate quadrature squeezed states of a moving mirror
in a Fabry-Perot cavity. This is achieved by exploiting the fact that when the
cavity is driven by an external field with a large detuning, the moving mirror
behaves as a parametric oscillator. We show that parametric resonance can be
reached approximately by modulating the driving field amplitude at a frequency
matching the frequency shift of the mirror. The parametric resonance leads to
an efficient generation of squeezing, which is limited by the thermal noise of
the environment.Comment: 4 pages, 2 figure
Single-particle machine for quantum thermalization
The long time accumulation of the \textit{random} actions of a single
particle "reservoir" on its coupled system can transfer some temperature
information of its initial state to the coupled system. This dynamic process
can be referred to as a quantum thermalization in the sense that the coupled
system can reach a stable thermal equilibrium with a temperature equal to that
of the reservoir. We illustrate this idea based on the usual micromaser model,
in which a series of initially prepared two-level atoms randomly pass through
an electromagnetic cavity. It is found that, when the randomly injected atoms
are initially prepared in a thermal equilibrium state with a given temperature,
the cavity field will reach a thermal equilibrium state with the same
temperature as that of the injected atoms. As in two limit cases, the cavity
field can be cooled and "coherently heated" as a maser process, respectively,
when the injected atoms are initially prepared in ground and excited states.
Especially, when the atoms in equilibrium are driven to possess some coherence,
the cavity field may reach a higher temperature in comparison with the injected
atoms. We also point out a possible experimental test for our theoretical
prediction based on a superconducting circuit QED system.Comment: 9 pages,4 figures
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