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We study the performance and limitations of a coherent interface between collective atomic states and single photons. A quantized spin-wave excitation of an atomic sample inside an optical resonator is prepared probabilistically, stored, and adiabatically converted on demand into a sub-Poissonian photonic excitation of the resonator mode. The measured peak single-quantum conversion efficiency of chi=0.84(11) and its dependence on various parameters are well described by a simple model of the mode geometry and multilevel atomic structure, pointing the way towards implementing high-performance stationary single-photon sources. 相似文献
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We demonstrate a broadband, thin-film, polarizing beam splitter based on an anisotropic diffraction grating composed of reactive mesogens (polymerizable liquid crystals). This achromatic polarization grating (PG) manifests high diffraction efficiency (approximately 100%) and high extinction ratio (> or = 1000:1) in both theory and experiment. We show an operational bandwidth Deltalambda/lambda0 approximately 56% (roughly spanning visible wavelength range) that represents more than a fourfold increase of bandwidth over conventional PGs (and significantly larger than any other grating). The diffraction angle and operational region (visible, near-infrared, midwave infrared, and ultraviolet wavelengths) may be easily tailored during fabrication. The essence of the achromatic design is a stack of two chiral PGs with an opposite twist sense and employs the principle of retardation compensation. We fully characterize its optical properties and derive the theoretical diffraction behavior. 相似文献
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A high-efficiency, ultrabroadband dielectric internal reflection grating with rhombus-shaped grooves is designed by a rigorous coupled-wave analysis, and an effective method for predicting spectral bandwidths of gratings from their efficiency maps is presented. The grating can be fabricated from a single dielectric material, and its reflection diffraction efficiency of the -1st order can reach more than 0.99. More importantly, an ultrabroadband top-hat diffraction spectrum with efficiency exceeding 0.98 over 170 nm wavelength wide is achieved, which makes the gratings suitable for applications associated with broadband illumination, such as ultrashort pulses. 相似文献
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《Laser \u0026amp; Photonics Reviews》2017,11(1)
Microresonator‐based Kerr frequency comb (microcomb) generation can potentially revolutionize a variety of applications ranging from telecommunications to optical frequency synthesis. However, phase‐locked microcombs have generally had low conversion efficiency limited to a few percent. Here we report experimental results that achieve conversion efficiency ( on‐chip comb power excluding the pump) in the fiber telecommunication band with broadband mode‐locked dark‐pulse combs. We present a general analysis on the efficiency which is applicable to any phase‐locked microcomb state. The effective coupling condition for the pump as well as the duty cycle of localized time‐domain structures play a key role in determining the conversion efficiency. Our observation of high efficiency comb states is relevant for applications such as optical communications which require high power per comb line.
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V D'Ambrosio E Nagali CH Monken S Slussarenko L Marrucci F Sciarrino 《Optics letters》2012,37(2):172-174
In this work we experimentally implement a deterministic transfer of a generic qubit initially encoded in the orbital angular momentum of a single-photon to its polarization. Such a transfer of quantum information, which is completely reversible, has been implemented adopting an electrically tunable q-plate device and a Sagnac interferometer with a Dove prism. The adopted scheme exhibits high fidelity and low losses. 相似文献
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We show that pairs of atoms optically excited to the Rydberg states can strongly interact with each other via effective long-range dipole-dipole or van der Waals interactions mediated by their nonresonant coupling to a common microwave field mode of a superconducting coplanar waveguide cavity. These cavity mediated interactions can be employed to generate single photons and to realize in a scalable configuration a universal phase gate between pairs of single photon pulses propagating or stored in atomic ensembles in the regime of electromagnetically induced transparency. 相似文献
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L. Nedelchev D. Ivanov N. Berberova V. Strijkova D. Nazarova 《Optical and Quantum Electronics》2018,50(5):212
Azopolymers are one of the most efficient materials able to record the polarization state of light. They have numerous applications, such as data storage and diffractive optical elements with unique polarization properties. An essential parameter for each diffractive element is its diffraction efficiency η. In order to optimize the recording conditions and obtain high-efficient polarization holographic gratings, in the present work we study the dependence of the diffraction efficiency on the recording angle and thickness of a series of azopolymer layers. Three recording angles are used ??10°, 20° and 30° and three series of thin films with thicknesses 470, 850 and 2400 nm from the water-soluble azopolymer PAZO. The gratings are inscribed by two plain waves with left and right circular polarization from a He-Cd gas laser (442 nm). The diffraction efficiency of the gratings is probed with a right hand circularly polarized beam from a probe laser with wavelength 635 nm. The kinetics of diffraction efficiency η(t) in the +?1 diffraction order are presented and compared. Our experimental results indicate that highest diffraction efficiency (more than 40%) is obtained for the sample with thickness 2400 nm and for recording angle 10°. As the holographic recording in azopolymers is usually accompanied by formation of surface relief gratings, the surface topography of the recorded samples is also investigated by atomic force microscopy. 相似文献
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In a previous paper [Nat. Photon. 5, 166 (2011)], we reported on a planar dielectric antenna that achieved 96% efficiency in collecting the photons emitted by a single molecule. In that work, the transition dipole moment of the molecule was set perpendicular to the antenna plane. Here, we present a theoretical extension of that scheme that reaches collection efficiencies beyond 99% for emitters with arbitrarily oriented dipole moments. Our work opens important doors in a wide range of contexts including quantum optics, quantum metrology, nanoanalytics, and biophysics. In particular, we provide antenna parameters to realize ultrabright single-photon sources in high-index materials such as semiconductor quantum dots and color centers in diamond, as well as sensitive detection of single molecules in nanofluidic devices. 相似文献
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Zygmunt Lalak 《Physics letters. [Part B]》1990,240(3-4):327-332
Light scalar states are generically present in a large class of stringy models. It is shown that they explain the polarized photon fluxes emitted from regions of the Universe filled with a strong magnetic field. We propose a specific scenario for sufficient emission in a realistic model. 相似文献
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We study numerically the photon input efficiency of silicon solar cells due to gold plasmonic nanoparticles deposited on the cells. At low densities, when collective effects in light scattering by the nanoparticle ensemble are negligible, the absorption dependence increases linearly for a significant range of the solar spectrum. Collective effects lead to the input efficiency saturates, reaches its maximum and then decreases with nanoparticle density. The maximal input efficiency depends on the photon wavelength, nanoparticle shape and size, their distance to the cell, and the cell thickness, and can reach ~ 95% in thick solar cells. Finally, we show that aluminum nanoparticles improve the input efficiency in comparison with gold nanoparticles. 相似文献
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宽调谐高效率的BBO光参量振荡器 总被引:2,自引:2,他引:0
本文报道用354.7nm泵浦的单共振BBO脉冲光参量振荡器在413~661nm和2513~765nm波段内获得了可调谐的振荡输出,最高总能量转换效率达52%;文中还讨论了输出特性。 相似文献
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《中国物理 B》2015,(6)
We experimentally demonstrate multiple frequency conversion via atomic spin coherence of storing a light pulse in a doped solid.The essence of this multiple frequency conversion is four-wave mixing based on stored atomic spin coherence.Through electromagnetically induced transparency,an input probe pulse is stored into atomic spin coherence by modulating the intensity of the control field.By using two different control fields to interact with the coherently prepared medium,the stored atomic spin coherence can be transformed into three different information channels.Multiple frequency conversion is implemented efficiently by manipulating the spectra of the control fields to scatter atomic spin coherence.This multiple frequency conversion is expected to have potential applications in information processing and communication network. 相似文献
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The regimes of high conversion efficiency of cascade triplers of optical radiation are theoretically investigated. A conversion
efficiency of 100% for plane waves can be reached. Analytical expressions for the wave amplitudes in this case are given.
The conversion efficiencies for a laser beam with Gaussian distribution of the amplitude in space and time are numerically
computed. The maximum efficiency for such a beam is about 50%. Some experimental situations are discussed. 相似文献