33,815 research outputs found
Synchronized Switching in a Josephson Junction Crystal
We consider a superconducting coplanar waveguide resonator where the central
conductor is interrupted by a series of uniformly spaced Josephson junctions.
The device forms an extended medium that is optically nonlinear on the single
photon level with normal modes that inherit the full nonlinearity of the
junctions but are nonetheless accessible via the resonator ports. For specific
plasma frequencies of the junctions a set of normal modes clusters in a narrow
band and eventually become entirely degenerate. Upon increasing the intensity
of a red detuned drive on these modes, we observe a sharp and synchronized
switching from low occupation quantum states to high occupation classical
fields, accompanied by a pronounced jump from low to high output intensity.Comment: 13 pages, 5 figure
A VLA Study of 15 3CR Radio Galaxies
We present VLA radio maps in total intensity and polarization at 1.4, 4.9 and
8.4 GHz of fifteen 3CR radio galaxies for which good maps showing the
large-scale radio structure have not previously been available. Previously
unknown cores are detected in several sources and a bright one-sided jet in 3C
287.1 is mapped for the first time; several other jet-like features are also
imaged. Total and core fluxes are tabulated and radio core positions are listed
and compared to optical positions. The galaxy at the optical position listed
for 3C 169.1 is found to lie farther from the radio core position than another
dimmer, bluer galaxy. We discuss individual sources in some detail.Comment: 35 pages, 22 figures but 35 separate Postscript figure files, AASTeX,
Accepted for publication in the Astrophysical Journal Supplemen
Many Body Physics with Coupled Transmission Line Resonators
We present the Josephson junction intersected superconducting transmission
line resonator. In contrast to the Josephson parametric amplifier, Josephson
bifurcation amplifier and Josephson parametric converter we consider the regime
of few microwave photons. We review the derivation of eigenmode frequencies and
zero point fluctuations of the nonlinear transmission line resonator and the
derivation of the eigenmode Kerr nonlinearities. Remarkably these
nonlinearities can reach values comparable to Transmon qubits rendering the
device ideal for accessing the strongly correlated regime. This is particularly
interesting for investigation of quantum many-body dynamics of interacting
particles under the influence of drive and dissipation. We provide current
profiles for the device modes and investigate the coupling between resonators
in a network of nonlinear transmission line resonators.Comment: submitted to the proceedings of the CEWQO 2012 conferenc
Master equation approach for interacting slow- and stationary-light polaritons
A master equation approach for the description of dark-state polaritons in
coherently driven atomic media is presented. This technique provides a
description of light-matter interactions under conditions of
electromagnetically induced transparency (EIT) that is well suited for the
treatment of polariton losses. The master equation approach allows us to
describe general polariton-polariton interactions that may be conservative,
dissipative or a mixture of both. In particular, it enables us to study
dissipation-induced correlations as a means for the creation of strongly
correlated polariton systems. Our technique reveals a loss mechanism for
stationary-light polaritons that has not been discussed so far. We find that
polariton losses in level configurations with non-degenerate ground states can
be a multiple of those in level schemes with degenerate ground states
Migration of bosonic particles across a Mott insulator to superfluid phase interface
We consider a boundary between a Mott insulator and a superfluid region of a
Bose-Hubbard model at unit filling. Initially both regions are decoupled and
cooled to their respective ground states. We show that, after switching on a
small tunneling rate between both regions, all particles of the Mott region
migrate to the superfluid area. This migration takes place whenever the
difference between the chemical potentials of both regions is less than the
maximal energy of any eigenmode of the superfluid. We verify our results
numerically with DMRG simulations and explain them analytically with a master
equation approximation, finding good agreement between both approaches. Finally
we carry out a feasibility study for the observation of the effect in coupled
arrays of micro-cavities and optical lattices.Comment: 5 pages, 6 figures, to appear in Phys. Rev. Let
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