共查询到20条相似文献,搜索用时 15 毫秒
1.
If two initially coherent light fields with the frequencies ω and 2ω, which have been produced by a second harmonic generator, pass a degenerate parametric amplifier photon-anticorrelation effects can develop. We calculate the time-development of the photon distribution for the signal wave by treating both fields quantum mechanically. 相似文献
2.
We experimentally demonstrate generation of bright sub-Poissonian light by means of parametric deamplification in a phase-sensitive fiber amplifier that is based on a balanced nonlinear Sagnac interferometer. On direct detection, the photocurrent noise falls below the shot-noise limit by (0.6 +/- 0.2) dB (1.4 dB when corrected for detection losses). To observe the noise reduction we employed a scheme that used two orthogonally polarized pulses to cancel the noise that arises from the predominantly polarized guided-acoustic-wave Brillouin scattering in the fiber. We also present a simplified semiclassical theory of quantum-noise suppression by this amplifier, which is found to be in good agreement with the experimental results. 相似文献
3.
M. Sebawe Abdalla 《Physica A》1994,210(3-4):461-475
From the quantum mechanics and the quantum optics point of view the problem of the time-dependent Hamiltonian which describes the degenerate parametric amplifier is presented. Under a certain integrability condition the solution of the Heisenberg equations of motion is given. The wave function for both the Schrödinger picture and quasi-coherent states, as well as the Green's function is obtained. The Glauber second order correlation function, and the squeezing and higher order squeezing is examined. The quasi-probability distribution function is also considered. 相似文献
4.
An analysis of the degenerate parametric amplifier including the quantisation of pump and signal modes is presented. It is shown that the fluctuations in one quadrature of the signal mode may be reduced at most by a factor of two. This is in contradistinction to analyses where the pump field is treated classically which overestimate the reduction in fluctuations possible. 相似文献
5.
The aim of this paper is to study the squeezing and statistical properties of the light produced by a degenerate three-level laser whose cavity contains a degenerate parametric amplifier. In this quantum optical system the top and bottom levels of the three-level atoms injected into the laser cavity are coupled by the pump mode emerging from the parametric amplifier. For a linear gain coefficient of 100 and for a cavity damping constant of 0.8, the maximum intracavity squeezing is found at steady state and at threshold to be 93%. 相似文献
6.
Huynh A Tignon J Larsson O Roussignol P Delalande C André R Romestain R Le Si Dang 《Physical review letters》2003,90(10):106401
We studied the pump coherent dynamics in a II-VI microcavity parametric amplifier, using angle-resolved four-wave mixing. The polariton parametric amplification is found to result in a strong quenching and saturation of the pump coherence lifetime above the threshold. For the polariton scattering processes that remain below the amplification threshold, we find an angle-dependent collision broadening associated with the efficiency of the polariton scattering towards the excitonic reservoir. 相似文献
7.
We analyze the coherence properties of a partially coherent optical field emerging from two pinholes in a plane opaque screen. We show that at certain pairs of points in the region of superposition the light is fully coherent, regardless of the state of coherence of the light at the pinholes. In particular, this result also holds if each pinhole is illuminated by a different laser. 相似文献
8.
Photon-number distributions for parametric fluorescence from a nondegenerate optical parametric amplifier are measured with a novel self-homodyne technique. These distributions exhibit the thermal-state character predicted by theory. However, a difference between the fluorescence gain and the signal gain of the parametric amplifier is observed. We attribute this difference to a change in the signal-beam profile during the traveling-wave pulsed amplification process. 相似文献
9.
V. O. Martynov V. A. Mironov L. A. Smirnov 《Bulletin of the Russian Academy of Sciences: Physics》2018,82(1):25-29
The quantum dynamics of an optical parametric oscillator under conditions of partially coherent pumping is considered. It is shown that if the pumping amplitude strongly exceeds a threshold value, the average number of emitted photons coincides with the estimate of the classical approximation, but the quantum state of light turns out to be entangled. Even though pumping noises reduce the magnitude of this entanglement, quantum correlations are not completely eliminated. 相似文献
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11.
A Hamiltonian model that includes two-photon interaction with a two-level atom and a degenerate parametric amplifier is considered. By invoking a canonical transformation an exact solution of the wave function in the Schrödinger picture is obtained. The result presented in this context is employed to discuss the purity, the entropy squeezing, and the variance squeezing, in addition to the normal squeezing. It has been shown that the existence of the second harmonic generation leads to reduction in the squeezing amount for all quadrature variances and we found that as the value of the coupling parameter λ2 increases the squeezing phenomenon gets more apparent. Further we have also considered the Q-function as an example of the quasi-probability distribution. 相似文献
12.
We investigate experimentally the absorptive and dispersive properties of the triple-resonant optical parametric amplifier (OPA) for the degenerate subharmonic field. In the experiment the subharmonic field is utilized as the probe field and the harmonic wave as the pump field. We demonstrate that the electromagnetically induced transparency (EIT)-like effect can be simulated in the triple-resonant OPA when the cavity linewidth for the harmonic wave is narrower than that for the subharmonic field. However, this phenomenon cannot be observed in a double-resonant OPA. The narrow transparency window appears in the reflected field. Especially in the measured dispersive spectra of the triple-resonant OPA, a very steep variation of the dispersive profile of the subharmonic field is observed, which can result in a slow light as that observed in an atomic EIT medium. 相似文献
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14.
相干光经湍流传输引起光强闪烁效应,理论研究表明利用部分相干光可降低该影响,而相关的实验验证鲜有报道。利用水介质的对流湍流池模拟产生了Rytov方差为0.04~0.16的湍流,进行了弱起伏区湍流中部分相干光及相干光的传输实验,由接收光强计算出其光强闪烁指数随湍流Rytov方差的变化关系。实验结果表明:随着湍流强度的增加,部分相干光与相干光的闪烁效应均增强,但部分相干光的闪烁指数小于相干光。将实验数据与Andrews等人建立的闪烁指数理论模型进行比较,得出了较为一致的结论。 相似文献
15.
相干光经湍流传输引起光强闪烁效应,理论研究表明利用部分相干光可降低该影响,而相关的实验验证鲜有报道。利用水介质的对流湍流池模拟产生了Rytov方差为0.04~0.16的湍流,进行了弱起伏区湍流中部分相干光及相干光的传输实验,由接收光强计算出其光强闪烁指数随湍流Rytov方差的变化关系。实验结果表明:随着湍流强度的增加,部分相干光与相干光的闪烁效应均增强,但部分相干光的闪烁指数小于相干光。将实验数据与Andrews等人建立的闪烁指数理论模型进行比较,得出了较为一致的结论。 相似文献
16.
A. W. Domański D. Budaszewski M. Sierakowski T. R. Woliński 《Opto-Electronics Review》2006,14(4):305-310
In the paper we present results of analysis of partially coherent light depolarization in two types of liquid crystals possessing
linear birefringence controlled by temperature and external electric field changes. Some experimental results of degree of
polarization measurements for different light sources as a superluminescent diode and a laser diode are also presented. 相似文献
17.
A condition for the complete destructive interference of partially coherent fields emerging from pinholes in an opaque screen is derived, with the assumption of symmetry in both their geometric positions and coherence properties. We use this condition to theoretically investigate the simultaneous production of phase singularities of the optical field and of the spectral degree of coherence. We find that in cases where the number of point sources is even, a new type of mixed field/correlation singularity is observed. 相似文献
18.
We describe a novel external light control element that is capable of stabilizing both the amplitude and the frequency of an optical input field. A demanding application of this electro-optical parametric oscillator, conversion of incoherent inputs into coherent, phase-trackable outputs with small residual intensity modulation, is reported. Estimations show that commercially available light-emitting diodes have the potential to act as pump sources, although the incoherent optical input field used in these initial experiments was prepared by filtering of the coherent emission of a laser diode. 相似文献
19.
V.?A.?Banakh V.?V.?Zhmylevski? A.?B.?Ignat’ev V.?V.?Morozov I.?N.?Smalikho 《Optics and Spectroscopy》2010,108(1):107-116
The possibility of compensating distortions of the initial wavefront of a partially coherent beam by the backscattered radiation
power is analyzed. A new algorithm for controlling the flexible mirror by the signal of the volume atmospheric scattering
is proposed and its efficiency is studied. It is shown that the developed algorithm makes it possible to considerably reduce
the compensation time of distortions compared to the gradient method. 相似文献