Related papers: Slow Light in a Bragg Waveguide
We observe pulse delays of up to twenty times the input pulse duration when 200-ps laser pulses pass through a hot Rb 85 vapor cell. The pulse peak travels with a velocity equal to c/20, and the energy transmission is 5%. For pulses with…
Wave propagation in spatially periodic media, such as photonic crystals, can be qualitatively different from any uniform substance. The differences are particularly pronounced when the electromagnetic wavelength is comparable to the…
We investigate the nonlinear response of photonic crystal waveguides with suppressed two-photon absorption. A moderate decrease of the group velocity (~ c/6 to c/15, a factor of 2.5) results in a dramatic (30x) enhancement of three-photon…
We present an experimental measurement of the refractive index of high density Rb vapor in a gaseous atomic nanolayer. We use heterodyne interferometry to measure the relative phase shift between two copropagating laser beams as a function…
We present new observations of the gravitational lens (GL) system B1600+434, strongly suggesting that the lens is an edge-on spiral galaxy. These observations are used to constrain the mass model of the system, in particular the oblateness…
Free-electron lasers (FELs) can now generate temporally short, high power x-ray pulses of unprecedented brightness, even though their longitudinal coherence is relatively poor. The longitudinal coherence can be potentially improved by…
The minimal refractive index contrast to obtain a complete photonic bandgap (CPBG) in structured media was not identified so far. We address this problem by considering distributed quasicrystals in with arbitrary number and positions of…
Phase diagram of vortex states of high-$T_{\rm c}$ superconductors with {\it sparse and weak} columnar defects is obtained by large-scale Monte Carlo simulations of the three-dimensional anisotropic, frustrated XY model. The Bragg-Bose…
Slow light is a fascinating physical effect, raising fundamental questions related to our understanding of light-matter interactions as well as offering new possibilities for photonic devices. From the first demonstrations of slow light…
Transparent materials do not absorb light but have profound influence on the phase evolution of transmitted radiation. One consequence is chromatic dispersion, i.e., light of different frequencies travels at different velocities, causing…
In this paper, the forward and backward propagating modes in an optical waveguide structure namely the fiber Bragg filter also considered as a one dimensional photonic crystal, are analytically computed as a function of grating length for…
It is shown theoretically that an optical bottle resonator with a nanoscale radius variation can perform a multi-nanosecond long dispersionless delay of light in a nanometer-order bandwidth with minimal losses. Experimentally, a 3 mm long…
Almost twenty years ago the light was slowed down to less than $10^{-7}$ of its vacuum speed in a cloud of ultracold atoms of sodium. Upon a sudden turn-off of the coupling laser, a slow light pulse can be imprinted on cold atoms such that…
An effort was conducted to study temporal soliton pulse propagation in silicon nano-waveguides. These nonlinear phenomenas were studied both numerically and experimentally with phase-resolved Frequency Resolved Optical Gating. Soliton pulse…
The slowdown of optical pulses due to quantum-coherence effects is investigated theoretically for an "active material" consisting of InGaAs-based double quantum-dot molecules. These are designed to exhibit a long lived coherence between two…
Nanoscale heterogeneity (including size, shape, strain, and defects) significantly impacts material properties and how they function. Bragg coherent x-ray imaging methods have emerged as a powerful tool to investigate, in three-dimensional…
Contemporary observational and theoretical studies on the temporal nature of microscopic measurements renewed the discussion about the fundamental constants, leading to the possibility of light speed variation and superluminal pulse…
Multi-photon Bragg diffraction is a powerful method for fast, coherent momentum transfer of atom waves. However, laser noise, Doppler detunings, and cloud expansion limit its efficiency in large momentum transfer (LMT) pulse sequences. We…
We demonstrate, by theory and experiment, the ultrafast tilting of the dispersion curve of a photonic-crystal waveguide following the absorption of a femtosecond pump pulse. By shaping the pump-beam cross section with a nanometric shadow…
In this paper, we investigate the propagation of a weak optical probe pulse in an f-deformed Bose- Einstein condensate (BEC) of a gas with the -type three- level atoms in the electromagnetically induced transparency (EIT) regime. We use an…