147,626 research outputs found
Entangling nanomechanical oscillators in a ring cavity by feeding squeezed light
A scheme is presented for entangling two separated nanomechanical oscillators
by injecting broad band squeezed vacuum light and laser light into the ring
cavity. We work in the resolved sideband regime. We find that in order to
obtain the maximum entanglement of the two oscillators, the squeezing parameter
of the input light should be about 1. We report significant entanglement over a
very wide range of power levels of the pump and temperatures of the
environment.Comment: 13 pages,5 figure
Reactive-Coupling-Induced Normal Mode Splittings in Microdisk Resonators Coupled to Waveguides
We study the optomechanical design introduced by M. Li et al. [Phys. Rev.
Lett. {\bf 103}, 223901 (2009)], which is very effective for investigation of
the effects of reactive coupling. We show the normal mode splitting which is
due solely to reactive coupling rather than due to dispersive coupling. We
suggest feeding the waveguide with a pump field along with a probe field and
scanning the output probe for evidence of reactive-coupling-induced normal mode
splitting.Comment: 4 pages,6 figure
Spontaneous spatial fractal pattern formation in absorptive systems
We predict, for the first time to our knowledge, that purely-absorptive nonlinearity can support spontaneous spatial fractal pattern formation. A passive optical ring cavity with a thin slice of saturable absorber is analyzed. Linear stability analysis yields threshold curves for Turing (static) instabilities with features proposed as characteristics of potential fractal pattern formation. Numerical simulations of the fully-nonlinear dynamics, with both one and two transverse dimensions, confirm theoretical predictions
Weak gravity conjecture constraints on inflation
We consider the gravitational correction to the coupling of the scalar
fields. Weak gravity conjecture says that the gravitational correction to the
running of scalar coupling should be less than the contribution from scalar
fields. For instance, a new scale sets a UV cutoff
on the validity of the effective theory. Furthermore, this
conjecture implies a possible constraint on the inflation model, e.g. the
chaotic inflation model might be in the swampland.Comment: 11 pages, 3 figs; monor corrections; some clarifying remarks added
and the final version for publication in JHE
Direct Evidence from Spitzer for a low-luminosity AGN at the center of the Elliptical Galaxy NGC 315
We present the {\it Spitzer} Space Telescope InfraRed Array Camera (IRAC) and
Multiband Imaging Photometer (MIPS) observations of the elliptical galaxy NGC
315. After removal of the host galaxy's stellar emission, we detected for the
first time an infrared-red nucleus in NGC 315. We measured the spectral energy
distribution (SED) for this active nucleus with wavelength range covering from
radio to X-ray, and obtained the bolometric luminosity of , corresponding to an extremely low Eddington
ratio (L/L) of 4.97 10. Our results confirm that
the physical nature of the nucleus of NGC 315 is a low-luminosity AGN,
consistent with the recent optical and {\it Chandra} X-ray observations.Comment: 4 pages, accepted for publication in ApJ Letter
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