2,978 research outputs found
Perfect imaging: they don't do it with mirrors
Imaging with a spherical mirror in empty space is compared with the case when
the mirror is filled with the medium of Maxwell's fish eye. Exact
time-dependent solutions of Maxwell's equations show that perfect imaging is
not achievable with an electrical ideal mirror on its own, but with Maxwell's
fish eye in the regime when it implements a curved geometry for full
electromagnetic waves
Fiber-optical analogue of the event horizon
The physics at the event horizon resembles the behavior of waves in moving
media. Horizons are formed where the local speed of the medium exceeds the wave
velocity. We use ultrashort pulses in microstructured optical fibers to
demonstrate the formation of an artificial event horizon in optics. We observed
a classical optical effect, the blue-shifting of light at a white-hole horizon.
We also show by theoretical calculations that such a system is capable of
probing the quantum effects of horizons, in particular Hawking radiation.Comment: MEDIA EMBARGO. This paper is subject to the media embargo of Scienc
Stable operation of a synchronously pumped colliding-pulse mode-locked ring dye laser
Pulses of 100-fsec duration are obtained by synchronous pumping of a colliding-pulse ring dye laser with a mode-locked Ar+-ion laser. Stable operation of the synchronously pumped colliding-pulse mode-locked laser over hours was obtained by a suitable choice of the distance between the gain and the absorber in combination with an appro-priate pump-pulse sequence. Passive mode locking of a ring dye laser by the inter-action of two counterpropagating pulses in a thin sat-urable absorber (colliding-pulse mode locking) yields femtosecond laser pulses. ' In these lasers the gain medium (Rhodamine 6G) is pumped by a cw Ar+-ion laser. The saturable absorber (DODCI, 3,3-diethyl-oxadicarbocyanine iodide) synchronizes two counter-propagating pulses meeting in the absorber jet stream. The colliding pulses form a transient grating, which synchronizes and stabilizes the pulses.2 In order to ensure equal amplification for both counterpropagatin
Non-Gaussian states from continuous-wave Gaussian light sources
We present a general analysis of the state obtained by subjecting the output
from a continuous-wave (cw) Gaussian field to non-Gaussian measurements. The
generic multimode state of cw Gaussian fields is characterized by an infinite
dimensional covariance matrix involving the noise correlations of the source.
Our theory extracts the information relevant for detection within specific
temporal output modes from these correlation functions . The formalism is
applied to schemes for production of non-classical light states from a squeezed
beam of light
Luneburg lens in silicon photonics
The Luneburg lens is an aberration-free lens that focuses light from all directions equally well. We fabricated and tested a Luneburg lens in silicon photonics. Such fully-integrated lenses may become the building blocks of compact Fourier optics on chips. Furthermore, our fabrication technique is sufficiently versatile for making perfect imaging devices on silicon platforms. (C) 2011 Optical Society of AmericaPublisher PDFPeer reviewe
Perfect imaging with geodesic waveguides
Transformation optics is used to prove that a spherical waveguide filled with
an isotropic material with radial refractive index n=1/r has radial polarized
modes (i.e. the electric field has only radial component) with the same perfect
focusing properties as the Maxwell Fish-Eye lens. The approximate version of
that device using a thin waveguide with a homogenous core paves the way to
experimentally prove perfect imaging in the Maxwell Fish Eye lens
Collimating lenses from non-Euclidean transformation optics
Based on the non-Euclidean transformation optics, we design a thin
metamaterial lens that can achieve wide-beam radiation by embedding a simple
source (a point source in three-dimensional case or a line current source in
two-dimensional case). The scheme is performed on a layer-by-layer geometry to
convert curved surfaces in virtual space to flat sheets, which pile up and form
the entire lens in physical space. Compared to previous designs, the lens has
no extreme material parameters. Simulation results confirm its functionality.Comment: 12 pages, 6 figure
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