共查询到20条相似文献,搜索用时 500 毫秒
1.
2.
Noticeable positive Doppler effect on optical bistability in an N-type active Raman gain atomic system 下载免费PDF全文
We theoretically investigate the Doppler effect on optical bistability in an N-type active Raman gain atomic system inside an optical ring cavity.It is shown that the Doppler effect can greatly enhance the dispersion and thus create the bistable behaviour or greatly increase the bistable region,which has been known as the positive Doppler effect on optical bistability.In addition,we find that a positive Doppler effect can change optical bistability from the hybrid dispersion-gain type to a dispersive type. 相似文献
3.
研制了室温CdxZn1-xTe/ZNTe多量子阱法布里-珀罗腔光双稳器件,并在该器件上观察到皮秒一级的室温激子光双稳。研究结果表明,CdZn1-xTe/ZnTe多量子阱光双稳器件的光双稳值和对比度分别为363kW/cm^2和4:1。根据CfxZn1-xTe/ZnTe多量子阱的吸收谱和激子非线性理论,归结了CdxZn1-xTe/ZnTe多量子阱光双稳的主要非线性机理为激子的饱和和吸收。 相似文献
4.
We experimentally demonstrate strong optical bistability in a 2 μm continuous wave Tm,Ho:YLF laser with a bulk crystal. The laser is end-pumped by a 792 nm fiber-coupled laser diode. The bistable region is as wide as 1.6 W and the jump power at the turning point is as high as 82.5 mW when the temperature of the laser crystal is kept at 253 K. The influences of the cavity length and the transmission of the output coupler on the characteristics of optical bistability are obtained. The theoretical analysis shows that the bistable output in the Tm,Ho:YLF lasers comes from the combined effects of the nonlinear saturation of ground state reabsorption, the energy transfer upconversion, and the excited state absorption. 相似文献
5.
J. Liao X.J. Zhang F. Xu X.Z. Fan H.T. Wang N.B. Ming 《Applied physics. B, Lasers and optics》2002,75(8):865-869
Optical bistable behavior in a quasi-waveguide containing non-linear film has been experimentally investigated in several
publications in the past years; however, the physical mechanism for optical bistability has not been theoretically explained.
In the present letter, we propose a theoretical model and successfully explain the observed optical bistability of both the
reflected light and the scattered light (m-lines) in a non-linear quasi-waveguide. The optical bistability in the non-linear quasi-waveguide is due to the scattering-type
wavevector mismatch mechanism.
Received: 10 July 2002 / Revised version: 10 September 2002 / Published online: 20 December 2002
RID="*"
ID="*"Corresponding author. Fax: +86-25/359-5535, E-mail: htwang@nju.edu.cn 相似文献
6.
We study third harmonic generation in layered configuration when the fundamental exhibits bistable response. We consider two
geometries, namely, a Fabry-Perot cavity with reflection coatings and a distributed feedback structure with alternate nonlinear
layers. In both the cases for suitable choice of frequency, the power response at the fundamental frequency is bistable. We
show that bistability of the fundamental leads to a multivalued character of the generated third harmonic in both the forward
and backward directions. Moreover, we study frequency response in the case of the Fabry-Perot cavity and show that additional
structures arise in the generated third harmonic due to frequency bistability of the fundamental. Our calculations suggest
the possibility of an all optical switch at third harmonic frequency controlled by the parameters (like intensity, frequency)
of the fundamental. 相似文献
7.
8.
9.
10.
We have proposed a scheme for double-beam optical bistability in a tunnel-coupled asymmetric double quantum-well driven by two optical fields circulating inside two independently unidirectional ring cavities. In contrast to the single-cavity case where single-photon saturated absorption and self Kerr-nonlinearity are dominant, the two-photon absorption and cross phase modulation can be enhanced via tunneling induced interference and have an important influence to the formation of bistability. The bistable behavior can be controlled effectively via the system parameters such as the input and detuning of control field, the detuning of the probe field, Fano interference strength and cooperation parameter. Furthermore, the proposed scheme has the ability to manipulate the outputs of two optical cavities simultaneously. Due to the flexible design of semiconductor quantum well, our scheme is more practical than atomic system, therefore it can be utilized to achieve dual all-optical switching which has application in optical communication and computing. 相似文献
11.
We report successful optical realization of both logical and relational functionality using a multiple quantum well optical bistable device operating without external bias and a simple experimental setup. For the nonbiased optical bistability, we employed extremely shallow quantum wells and asymmetric Fabry-Perot cavity structure in self electro-optic effect device. The change between logical and relational mode was simply realized by controlling the intensity of the optical bias beam into devices following the basic operation principle of the optical bistability. 相似文献
12.
We investigate the nonlinear optical phenomena of the optical bistability and multistability via spontaneously generated coherence in an asymmetric double quantum well structure coupled by a weak probe field and a controlling field. It is shown that the threshold and hysteresis cycle of the optical bistability can be conveniently controlled only by adjusting the intensity of the SGC or the controlling field. Moreover, switching between optical bistability and multistability can be achieved. These studies may have practical significance for the preparation of optical bistable switching device. 相似文献
13.
We study the behavior of optical bistability (OB) in a triple semiconductor quantum well structure with tunnelling-induced interference, where the system is driven coherently by the probe laser inside the unidirectional ring cavity. The results show that we are able to control efficiently the bistable threshold intensity and the hysteresis loop by tuning the parameters of the system such as laser frequency and tunnelling-induced frequency splitting. This investigation can be used for the development of new types of nanoelectronic devices for realizing switching process. 相似文献
14.
V.I. Vlad 《Optics Communications》1982,41(6):411-416
An opto-electronic bistable device using a twisted nematic liquid crystal cell is described. The optical bistability characteristics of this device are used in a new liquid crystal light valve with bistability in cellular array structure. Experimental studies demonstrate the applications of such opto-electronic bistable devices in real-time optical information processing such as intensity limiting for contrast improvement and noise elimination, edge enhancement for pattern recognition, linear and nonlinear optical filtering (in spatial and spectral domains). 相似文献
15.
Controllable optical bistability in a three-mode optomechanical system with a membrane resonator 下载免费PDF全文
We study the optical bistability(OB) in a three-mode cavity optomechanical system, where an oscillating membrane of perfect reflection is inserted between two fixed mirrors of partial transmission. By investigating the behavior of steady state solutions, we find that the left and right cavities will exhibit the bistable behavior simultaneously in this optomechanical system by adjusting the left and right coupling fields. In addition, one can control the OB threshold and the width of the OB curve via adjusting the coupling strength, the detuning, and the decay rate. Moreover, we further illustrate the OB appearing in the cavity by the effective potential as a function of the position. 相似文献
16.
The conditions for the realization of absorption optical bistability under the simultaneous action of two (radiative and nonradiative) mechanisms of recombination of free charge carriers are investigated. It is shown that, in the diffusion mechanism of stream of free electrons from the beam axis, the temperature dependence of radiative recombination does not expand the temperature range of the thermostat in which the optical bistability occurs. A scheme is proposed with application of an external transverse electric field, which makes it possible to realize absorption optical bistability at any ambient temperature. An important advantage of this scheme is the conservation of the state of a bistable system after the action of a light pulse and a significant decrease in the energy spent on cooling of the medium. 相似文献
17.
J. A. Hermann J. N. Elgin P. L. Knight 《Zeitschrift für Physik B Condensed Matter》1982,45(3):255-258
We show that bistable behaviour in a two-photon resonant system within a cavity may be attributed to interactive mode-pulling via the two-photon optical Kerr effect and also to absorptive bleaching (atomic saturation). The interactive Kerr process may be regarded as giving rise to a new category of optical bistability. Moreover, a mechanism for the recently-predicted tristability can be found in terms of simultaneous competition between the interactive Kerr effect and bleaching. 相似文献
18.
In this paper the results of an analysis concerning the course of optical dispersive bistability in media with forced girotropy (the Faraday effect) are presented. It is shown that radiation transmitted through a non-linear Fabry-Perot cavity reveals, apart from bistability of the intensity, bistable states of polarization. The elliptically polarized transmission radiation changes bistably not only the value of proportion of the semiaxes of the polarization ellipse and the orientation angle of its major semi-axis, but also the direction of the rotation of its electric vector. 相似文献
19.
We demonstrate strong optical bistability in a 2 microm continuous-wave Tm,Ho:YLF laser pumped by a 792 nm laser diode near room temperature. The bistable region is as much as 100 mW wide at 283 K and can be controlled by the temperature of the laser crystal. The influence of crystal temperature on the characteristics of optical bistability is obtained. The influence of the pump-to-mode ratio on the bistable characteristics of the laser is also discussed. To our knowledge this is the first report of optical bistability effects in Tm,Ho:YLF lasers. 相似文献
20.
In this paper, we demonstrate experimentally switching a cantilever between its optomechanical bistable states in a low finesse optical cavity. Our experiment shows that the deformation of cantilever can be manipulated by tuning the cavity resonance. When the laser power increases across the threshold value of 110 ?W, optomechanical bistability is induced by strong static photothermal backaction at room temperature. Numerical calculation revealed that the bistable effect originates from the multi-well potential created via the optomechanical interaction. Switching of the cantilever between the bistable states was achieved by tuning the cavity to the corresponding boundaries of the bistable region, where the barrier between the bistable states vanishes. 相似文献