共查询到20条相似文献,搜索用时 78 毫秒
1.
We investigate the propagation of intense probe pulses in a lifetime broadened Λ-type three-level atomic system with a configuration of electromagnetically induced transparency. We find that ultraslow optical solitons formed by a balance between dispersion and nonlinearity can be stored and retrieved in the system by switching off and on a control field. Such pulses are robust during storage and retrieval, and hence may have potential applications in optical and quantum information processing. 相似文献
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Tunable All-Optical Filtering and Buffering in a Coupled Quantum Dot-Planar Photonic Crystal Structure 下载免费PDF全文
We theoretically investigate controlled tunable all-optical filtering and buffering of optical pulses in a hybrid nano-photonic structure, where a single quantum dot (QD) embedded in a photonic crystal nanocavity is sidecoupled between a bare nanocavity and a photonic crystal waveguide. We demonstrate that there is a sharp low-loss transmission peak in the transmission spectrum under even low QD-nanocavity coupling strength and the input optical pulses can be delayed up to several hundred picoseconds within the dephasing time of the QD. The filtering regime can be shifted readily by manipulating the detuning between the QD excitonic transition frequency and resonant frequency of the nanocavity mode, which can be explored in future for on-chip all-optical logic and signal processing. 相似文献
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Atomic Interaction Effects on Electromagnetically Induced Transparency and Slow Light in Ultracold Bose Gas 下载免费PDF全文
We investigate electromagnetically induced transparency and slow group velocity of light in ultracold bose gas with a two-photon Raman process,The properties of electromagnetically induced transparency and light speed can be changed by controlling the atomic interaction.Atomic interaction can be used as a knob to control the optical properties of atomic media.This can be realized in experiment by using the Feshbach resonance technique. 相似文献
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Large Bandwidth Optical Limiting by Kerr Medium Doped One-Dimensional Coupled Cavity Optical Waveguides 总被引:2,自引:0,他引:2 下载免费PDF全文
We present a new method to realize large bandwidth optical limiting using Kerr nonlinearity doped one-dimensional coupled cavity optical waveguides (CCOWs). When the incident intensity is weak, the structure is a perfect CCOW that supports a high transmission band. When the intensity is increased, the Kerr effects change the refractive index of the Kerr cavity which results in a large decrease of transmission coefficients in the whole band. We numerically analyse the limiter using the nonlinear transfer matrix method and nonlinear finite difference in time domain method. Optical limiting effects are observed in the whole transmission band, and optimization methods are also discussed. 相似文献
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We report the experimental demonstration of an ultranarrow bandwidth atomic filter by optically induced polarization rotation in multilevel electromagnetically induced transparency systems in hot Rb vapor. With a coupling intensity of 2.3 W/cm^2, the filter shows a peak transmission of 33.2% and a bandwidth of 10 MHz. By altering the coupling frequency, a broad tuning range of several Doppler linewidths of the D1 line transitions of STRb atoms can be obtained. The presented atomic filter has useful features of ultranarrow bandwidth, and the operating frequency can be tuned resonance with the atomic transition. Such narrowband tunable atomic filter can be used as an efficient noise rejection tool in classical and quantum optical applications. 相似文献
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We investigate theoretically two-photon absorption spectroscopy modified by a control field in a confined Y-type four-level system. Dicke-narrowing effect occurs both in two-photon absorption lines and the dips of transparency against two-photon absorption due to enhanced contribution of slow atoms. We also find that the suppression and the enhancement of two-photon absorption can be modified by changing the strength of the control field and the detuning of three laser fields. This control of two-photon absorption may have some applications in information processing and optical devices. 相似文献
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The coupled resonator-induced transparency(CRIT) phenomenon, which is analogous to electromagnetically induced transparency in atomic systems, can occur in an original integrated optical resonator system due to the coherent interference of the coupled optical resonators. The system was composed of three ring resonators on silicon, each with the same cavity size, and the optical coupling to the input and output ports was achieved using grating with a power coupling efficiency of 36%. A CRIT resonance whose spectrum shows a narrow transparency peak with a low group velocity was demonstrated.The quality factor of the ring resonator can attain a value up to 6×10~4, and the harmonic wavelength can be controlled by adjusting the temperature. The through and drop transmission spectra of the resonator are reconciled well with each other and also consistent well with the theoretical analysis. 相似文献
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Controlling multiple optomechanically induced transparency in the distant cavity-optomechanical system 下载免费PDF全文
We theoretically investigate a two-cavity optomechanical system in which each optical cavity couples to a mechanical resonator via radiation pressure force,and the two optical cavities couple to each other via a distant waveguide.Our study shows that the multiple optomechanically induced transparency can be observed from the output field at the probe frequency.The number and width of the transparent windows can be tuned by the classical driving power Pl.We also analyze the distance of the two outermost transparency windows,which shows a linear relation with the parameters Pl andλ.Our approach is feasible for controlling multipartite induced transparency,which represents a valuable step towards quantum networks with photonic and phononic circuits. 相似文献
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Surface plasmon resonance (SPR) is obtained by exciting the surface plasmon (SP) at the metal and dielectric interface, which can greatly enhance the extraordinary optical transmission (EOT) through a nanoslit milled in the metal film. We present a structure with a 50-nm-wide silver nanoslit for EOT by coupling light into the dielectric interlayer between periodic strips and a metal film. When the period of the metallic strips is equal to the wavelength of the SPR, the transmission efficiency of 187.6 through the nanoslit is enhanced. The metallic strip width over the nanoslit is optimized to improve transmission efficiency, and the maximal efficiency of 204.3 is achieved. 相似文献
10.
Using Schrodinger-Maxwell formalism, we propose and analyze a continuous-wave four-wave mixing (FWM) scheme for the generation of coherent light in a six-level atomic system based on electromag-netically dual induced transparency. We derive the corresponding explicit analytical expressions for the generated mixing field. We find that the scheme greatly enhances FWM production efficiency and is also capable of inhibiting and delaying the onset of the detrimental three-photon destructive interference by choosing the proper decay rate in the second electromagnetically induced transparency (EIT) process. In addition, such an optical process also provides possibilities for producing short-wave-length coherent radiation at low pump intensities. 相似文献
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Yasuhiro Suzuki Yuichi Tohmori Kazutoshi Kato Mitsuo Fukuda Hiromi Oohashi Satoshi Sekine Naoto Uchida Hiromu Toba Masaharu Horiguchi Toshihiko Sugie Yasuhumi Yamada 《Optical and Quantum Electronics》1998,30(3):141-159
Cost-effectiveness is essential in developing optical access network systems. To reduce system costs, both improved system and component technologies are required. Reducing the costs of optical devices and modules in an optical network unit is especially necessary. In this paper, the requirements for optical devices in optical access networks and modules are clarified. Moreover, we also review the recent progress in technologies for semiconductor optical devices and hybrid integration for low-cost optical modules in access networks. 相似文献
12.
Abstract In this article, light reflection spectrums for different one-dimensional multi-layer structures are obtained. Optical reflectivities for periodic, superperiodic, and quasiperiodic structures have been calculated using the transfer matrix method. PBGs of each structure have been obtained using the optical reflectivity pattern. From a comparison of reflectivity and standard dense wavelength division multiplexing grids, it is demonstrated that narrow and dense band filters can be built from generalized Fibonacci quasiperiodic structures. Reflectivity of these structures contains bands that meet the ITU-T dense wavelength division multiplexing standard. Reflectivity of other multi-layer structures has poor or less potential to be used in dense wavelength division multiplexing systems. 相似文献
13.
振镜扫描光学多道谱仪 总被引:1,自引:0,他引:1
以平面光栅单色仪和光学扫描振镜为基础研制一套具有高时间分辨能力的光学多道分析系统,并利用计算机进行实时控制与数据采集。实验表明:本系统在保持谱分辨的同时,时间分辨率达到10ms以内。 相似文献
15.
Diffractive optical elements such as the complementary Dammann gratings are incorporated for dynamic optical fiber splitting and combining. Experimental results of 1′8 dynamic optical couplings are presented. 相似文献
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Yihong Chen 《光学学报》2003,23(Z1)
Erbium doped fiber amplifier, Raman amplifier, and semiconductor optical amplifier are discussed. The applications of these amplifiers are reviewed. 相似文献
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提出了两种适用于光突发交换网的可编程光缓存器结构:交叉型和多端口开关型.两种结构都能满足突发包缓存的超长性和可变性的要求,且结构简单紧凑,成本低,可扩展.交叉型缓存器通过指定信号在每个子缓存模块的光纤环中的循环次数即能实现可变时间的延迟.多端口开关型缓存器通过指定信号在两个多端口开关相应端口与所接光纤延迟线组成的光纤环中的循环次数实现可变时间的延迟.仿真结果表明,两种可编程光缓存器都能对光突发包实现ns级指定时间延迟,可用于解决光突发交换网突发包的冲突问题. 相似文献