Optically Tunable Photonic Stop Bands in Homogeneous Absorbing Media.

Resonantly absorbing media supporting electromagnetically induced transparency may give rise to specific periodic patterns where a light probe is found to experience a fully developed photonic band gap yet with negligible absorption everywhere. In ultracold atomic samples the gap is found to arise from spatial regions where Autler-Townes splitting and electromagnetically induced transparency alternate with one another and detailed calculations show that accurate and efficient coherent optical control of the gap can be accomplished. The remarkable experimental simplicity of the control scheme would ease quantum nonlinear optics applications

Atomic recoil effects in slow light propagation

We theoretically investigate the effect of atomic recoil on the propagation of ultraslow light pulses through a coherently driven Bose-Einstein condensed gas. For a sample at rest, the group velocity of the light pulse is the sum of the group velocity that one would observe in the absence of mechanical effects (infinite mass limit) and the velocity of the recoiling atoms (light-dragging effect). We predict that atomic recoil may give rise to a lower bound for the observable group velocities, as well as to pulse propagation at negative group velocities without appreciable absorption

Polarization qubit phase gate in driven atomic media

We present here an all--optical scheme for the experimental realization of a quantum phase gate. It is based on the polarization degree of freedom of two travelling single photon wave-packets and exploits giant Kerr nonlinearities that can be attained in coherently driven ultracold atomic media.Comment: 4 pages, 1 figure, in press on PR

Perfect absorption and no reflection in disordered photonic crystals

Understanding the effects of disorder on the light propagation in photonic devices is of major importance from both fundamental and applied points of view. Unidirectional reflectionless and coherent perfect absorption of optical signals are unusual yet fascinating phenomena that have recently sparked an extensive research effort in photonics. These two phenomena, which arise from topological deformations of the scattering matrix S parameters space, behave differently in the presence of different types of disorder, as we show here for a lossy photonic crystal prototype with a parity-time antisymmetric susceptibility or a more general non-Hermitian one

Physics of excitonic quasiparticles: beyond conventional polaritons

Some aspects of post-conventional polariton physics are discussed. In the framework of quantum statistical properties we demonstrate that polaritons are intrinsically squeezed. The polariton squeezing is frequency tunable, and can be larger than that in usual atomic systems. The new phonoriton excitation, which gives rise to spectrum reconstruction, is reexamined on the basis of a simple model: threshold behavior, new gap structure and related properties are discussed

EVALUASI KEMAMPUAN KETERAMPILAN DASAR SEPAK BOLA PADA KLUB SSB BUMI MUDA SEDIA USIA 15 TAHUN ACEH TAMIANG TAHUN 2013

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Driving the atom by atomic fluorescence: analytic results for the power and noise spectra

We study how the spectral properties of resonance fluorescence propagate through a two-atom system. Within the weak-driving-field approximation we find that, as we go from one atom to the next, the power spectrum exhibits both sub-natural linewidth narrowing and large asymmetries while the spectrum of squeezing narrows but remains otherwise unchanged. Analytical results for the observed spectral features of the fluorescence are provided and their origin is thoroughly discussed.Comment: 13 pages, 5 figures; to be published in Phys. Rev. A Changed title and conten

Stormorken syndrome caused by a p.R304W STIM1 mutation: The first Italian patient and a review of the literature

Stormorken syndrome is a rare autosomal dominant disease that is characterized by a complex phenotype that includes tubular aggregate myopathy (TAM), bleeding diathesis, hyposplenism, mild hypocalcemia and additional features, such as miosis and a mild intellectual disability (dyslexia). Stormorken syndrome is caused by autosomal dominant mutations in the STIM1 gene, which encodes an endoplasmic reticulum Ca2+ sensor. Here, we describe the clinical and molecular aspects of a 21-year-old Italian female with Stormorken syndrome. The STIM1 gene sequence identified a c.910C T transition in a STIM1 allele (p.R304W). The p.R304W mutation is a common mutation that is responsible for Stormorken syndrome and is hypothesized to cause a gain of function action associated with a rise in Ca2+ levels. A review of published STIM1 mutations (n = 50) and reported Stormorken patients (n = 11) indicated a genotype-phenotype correlation with mutations in a coiled coil cytoplasmic domain associated with complete Stormorken syndrome, and other pathological variants outside this region were more often linked to an incomplete phenotype. Our study describes the first Italian patient with Stormorken syndrome, contributes to the genotype/phenotype correlation and highlights the possibility of directly investigating the p.R304W mutation in the presence of a typical phenotype