共查询到20条相似文献,搜索用时 15 毫秒
1.
《Physics letters. A》1999,251(5):294-296
We consider a “superluminal quantum Morse telegraph”, recently proposed by Garuccio, involving a polarization-correlated photon pair and a Michelson interferometer in which one of the mirrors is replaced by a phase-conjugating mirror (PCM). Superluminal information transfer in this scheme is precluded by the impossibility of distinguishing between unpolarized photons prepared by mixing linear polarization states or by mixing circular polarization states. 相似文献
2.
A simple geometry utilizing a laser-excited atomic beam as light source, and a nearby oscillating mirror, would permit the observation of a two-channel optical interference effect involving photons which can be localized predominantly in one channel by coincidence observations of the recoiling source atom. A sacrifice of the optimum conditions for photon interference is necessary even when photon localization in one channel is accomplished by an observation of the recoil atom. This necessity arises because the width of the slit defining the atomic beam, and with it the important optical source dimension, must be comparable to the optical wavelength to obtain the small uncertainty in initial total momentum needed for significant localization. Quantum mechanical calculations of the coincidence intensity and singles intensity as a function of mirror position are made for a source width of five quarter wavelengths and are compared to a classical optics calculation of the singles intensity. The coincidence intensity calculation, as expected, predicts a smaller interference effect than classical optics due to the photon localization. The singles intensity calculation also predicts the same reduction in the classical interference effect, as a consequence of the orthoganality of the final atom states. 相似文献
3.
We consider the interference of two photons with different colors in the context of a Hong-Ou-Mandel experiment, in which single photons enter each of the input ports of a beam splitter, and exit together in the same, albeit undetermined, output port. Such interference is possible if one uses an active (energy-non-conserving) beam splitter. We find scenarios in which one “red” and one “blue” photon enter the beam splitter, and either two red or two blue photons exit, but never one of each color. We show how the precise form of the active beam-splitter transformation determines in what way the spectral degrees of freedom of the input photons should be related to each other for perfect destructive interference of the different-color components in the output. We discuss two examples of active beam splitters: one is a gedanken experiment involving a moving mirror and the other is a more realistic example involving four-wave mixing in an optical fiber. 相似文献
4.
利用传输矩阵法研究了镜像异质三周期一维光子晶体中的光子局域态随单轴应力发生变化的特性. 对于镜像异质三周期光子晶体, 由于其镜像结构, 破坏了光子晶体的有序性, 产生了一个缺陷态, 使其在较宽的光子禁带中心有一个光子局域态透射峰. 研究表明: 当对镜像异质三周期光子晶体施加单轴应力时, 其中的光子局域态透射峰会随着应力的改变而发生剧烈的变化. 当外部微弱的机械应力施加到光子晶体上时, 对光子晶体形成一个拉伸应变, 拉伸应变引起光子晶体结构的变化, 进而大幅度影响光子局域态透射峰的透射率.结果表明: 透射峰的透射率明显受单轴应力的影响. 这些特性可为用此结构的光子晶体设计超高灵敏度压力传感器提供理论参考.
关键词:
光子晶体
单轴应力
光子局域态
传输矩阵 相似文献
5.
Extreme ultraviolet (EUV) optics play a key role in attosecond science since only with higher photon energies is it possible to achieve the wide spectral bandwidth required for ultrashort pulses. Multilayer EUV mirrors have been proposed and are being developed to temporally shape (compress) attosecond pulses. To fully characterize a multilayer optic for pulse applications requires not only knowledge of the reflectivity, as a function of photon energy, but also the reflected phase of the mirror. We develop the metrologies to determine the reflected phase of an EUV multilayer mirror using the photoelectric effect. The proposed method allows one to determine the optic's impulse response and hence its pulse characteristics. 相似文献
6.
J. W. Eslick Jr H. N. Pham C. Radu A. Puri 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2006,38(3):553-562
In this paper, we revisit the problem of quantum entanglement in an
oscillating macroscopic mirror previously studied by Marshall et al. consisting
of a modified Michelson interferometer where one of the mirrors is free to
oscillate about its center of mass. A photon incident upon the oscillating
mirror becomes entangled with the mirror, driving the mirror into a
superposition of quantum states. Once the photon and mirror decouple, the
mirror returns to its initial state. The purpose of our investigations was
to optimize the parameter regime, taking into consideration the current
state of technology and the demands imposed by the need to maintain a stable
environment in the presence of thermal noise. Optimization should not demand
ultra-low temperatures and this is reflected in our results. Our results also
show that if the separation between states is maintained at 10-14 m, the mirror size is reduced, making it easier to induce superposition in
the mirror. The critical nature of mirror reflectivity and its connection to
cavity decay rate was also revealed by our investigations. The results
obtained through our investigations could be useful in quantum error
correction, where decoherence negatively affects the results of computations
performed by quantum computers. Finally, we note that we are only concerned
with an isolated system, where no losses to the external environment occur
and any decoherence that occurs within the system remains internal to the
system; that is, any mention of decoherence refers specifically to
recoverable decoherence. 相似文献
7.
Mu-Tian Cheng Wei-Wei Zong Gen-Long Ye Xiao-San Ma Jia-Yan Zhang Bing Wang 《理论物理通讯》2016,65(6):767-771
We investigate theoretically single photon transport properties in coupled-resonator waveguide coupling with a nanocavity interacting with an external mirror. By using the discrete coordinates approach, transmission and reflection amplitudes of the propagating single photon in the waveguide are obtained. The influence of the coupling strength between the nanocavity and the external mirror on the single photon scattering spectra is discussed. We also extend the results to the waveguide with linear and quadratic form dispersion relations. 相似文献
8.
We report on the first observation of stimulated Raman scattering from a Lambda-type three-level atom, where the stimulation is realized by the vacuum field of a high-finesse optical cavity. The scheme produces one intracavity photon by means of an adiabatic passage technique based on a counterintuitive interaction sequence between pump laser and cavity field. This photon leaves the cavity through the less-reflecting mirror. The emission rate shows a characteristic dependence on the cavity and pump detuning, and the observed spectra have a subnatural linewidth. The results are in excellent agreement with numerical simulations. 相似文献
9.
We consider the coupling of the electromagnetic vacuum field with an oscillating perfectly-reflecting mirror in the nonrelativistic approximation. As a consequence of the frequency modulation associated to the motion of the mirror, low frequency photons are generated. We calculate the photon emission rate by following a nonperturbative approach, in which the coupling between the field sidebands is taken into account. We show that the usual perturbation theory fails to account correctly for the contribution of TM-polarized vacuum fluctuations that propagate along directions nearly parallel to the plane surface of the mirror. As a result of the modification of the field eigenfunctions, the resonance frequency for photon emission is shifted from its unperturbed value. 相似文献
10.
11.
Two photon absorption spectrum ofp-dichlorobenzene has been studied in the spectral region 497–552 nm (one photon wavelength). Bands involving several frequencies
of the excited electronic state not detected in the one photon absorption are seen. The observed two photon spectrum indicates
that the electronic transition retains, to a large extent, the salient features of the two photon absorption spectrum of benzene
and thus confirms chlorine as weak perturber (in the sense of Goodman and Rava [1]). 相似文献
12.
S. S. Popov M. G. Atlukhanov A. V. Burdakov M. Yu. Ushkova 《Optics and Spectroscopy》2016,121(1):160-163
A new, nonresonant approach to photon accumulation in a system of two spherical mirrors is demonstrated experimentally. A high accumulation coefficient is obtained experimentally, and sufficient efficiency of this technique for application in such areas as spectroscopy, photochemistry, and photon neutralization of negative-ion beams is demonstrated. The photon accumulation efficiency is determined mainly by mirror reflectivity. It is nearly independent of the quality of the coupled-in radiation and does not require very high precision in aligning optical elements. The experimentally obtained data agree with theoretical calculations. 相似文献
13.
A simple optical system delivering a tunable micrometer pink beam that can compensate for heat‐induced deformations 下载免费PDF全文
Ruben Reininger Zunping Liu Gilles Doumy Linda Young 《Journal of synchrotron radiation》2015,22(4):930-935
The radiation from an undulator reflected from one or more optical elements (usually termed `pink‐beam') is used in photon‐hungry experiments. The optical elements serve as a high‐energy cutoff and for focusing purposes. One of the issues with this configuration is maintaining the focal spot dimension as the energy of the undulator is varied, since this changes the heat load absorbed by the first optical element. Finite‐element analyses of the power absorbed by a side water‐cooled mirror exposed to the radiation emitted by an undulator at the Advanced Photon Source (APS) and at the APS after the proposed upgrade (APSU) reveals that the mirror deformation is very close to a convex cylinder creating a virtual source closer to the mirror than the undulator source. Here a simple optical system is described based on a Kirkpatrick–Baez pair which keeps the focus size to less than 2 µm (in the APSU case) with a working distance of 350 mm despite the heat‐load‐induced change in source distance. Detailed ray tracings at several photon energies for both the APS and APSU show that slightly decreasing the angle of incidence on the mirrors corrects the change in the `virtual' position of the source. The system delivers more than 70% of the first undulator harmonic with very low higher‐orders contamination for energies between 5 and 10 keV. 相似文献
14.
提出了一种由一对抛物面构成的超腔的技术方案,计算了超腔汇聚点处的总光子密度。利用康普顿散射理论对基于抛物面超腔的激光同步辐射及其光子产额进行了讨论和计算。结果表明:当超腔镜面的反射率等于99.99%时,在超腔碰撞点处的总光子数密度大约是初始激光束在碰撞点处光子数密度的5 000倍,对应康普顿垂直散射的光子产额大约是电子束与初始激光束在碰撞点处发生康普顿垂直散射时的5 000倍。 相似文献
15.
Takanori Kiyokura Fumihiko MAEDA Yoshio Watanabe Yoshinori Iketaki Koumei Nagai Yoshiaki Horikawa Masaharu Oshima Eiji Shigemasa Akira Yagishita 《Optical Review》2000,7(6):576-578
The throughput of a Schwarzschild objective using undulator synchrotron radiation was measured. Conventionally, the throughput was estimated from the squared reflectivity of one multilayer mirror and from the obstruction ratio. However, we evaluated the transmission ratio from the input and output photon flux using a precisely calibrated monochromatic beam from an undulator light source. It was found that the objective has a maximum throughput of 8.5% at a wavelength of 13.9 nm. 相似文献
16.
Photon correlations are investigated for a single laser-excited ion trapped in front of a mirror. Varying the relative distance between the ion and the mirror, photon correlation statistics can be tuned smoothly from an antibunching minimum to a bunchinglike maximum. Our analysis concerns the non-Markovian regime of the ion-mirror interaction and reveals the field establishment in a half-cavity interferometer. 相似文献
17.
L. V. Il’ichev 《JETP Letters》2013,97(6):307-310
An optomechanical scheme of the interaction between a photon subsystem, which consists of two quantum modes, and a mechanical oscillator mirror, which is also considered as a quantum system, has been proposed. The conditions of the appearance of the easily controllable bistability of the position of the mirror have been discussed. The modification of the scheme for ensuring the controllable bistability of the position of the cloud of the atomic Bose condensate is possible. 相似文献
18.
提出了一种由一对抛物面构成的超腔的技术方案,计算了超腔汇聚点处的总光子密度。利用康普顿散射理论对基于抛物面超腔的激光同步辐射及其光子产额进行了讨论和计算。结果表明:当超腔镜面的反射率等于99.99%时,在超腔碰撞点处的总光子数密度大约是初始激光束在碰撞点处光子数密度的5 000倍,对应康普顿垂直散射的光子产额大约是电子束与初始激光束在碰撞点处发生康普顿垂直散射时的5 000倍。 相似文献
19.
A new hyperbolic metamaterial based on a modified semiconductor Bragg mirror structure with embedded periodically arranged quantum wells is proposed. It is shown that exciton polaritons in this material feature hyperbolic dispersion in the vicinity of the second photonic band gap. Exciton–photon interaction brings about resonant nonlinearity leading to the emergence of nontrivial topological polaritonic states. The formation of spatially localized breather-type structures (oscillons) representing kink-shaped solutions of the effective Ginzburg–Landau–Higgs equation slightly oscillating along one spatial direction is predicted. 相似文献
20.
The geometrical-optical analysis of synchrotron radiation shows that it is possible to define a mirror able to focus all the emitted light by an electron storage ring on a single point lying anywhere in space, keeping unchanged the typical time patterns of the radiation. Because of the electron ultrarelativistic conditions, the electron “orbital path” is assimilated to an “underground bent photon path”. We prove then that the focusing condition is simply given by establishing the invariance of the photon path: “optical photon path” + “underground bent photon path” = constant. Some selected numerical examples show that it is possible to collect huge amounts of radiation producing extremely high excitation densities in a given small volume. 相似文献