ISSN:0950-0340    

DOI:10.1080/09500348714550711

出版商:Taylor & Francis Group    

年代:1987

数据来源: Taylor

摘要:

In this paper we review the current state of progress in research on squeezed light. We discuss the basic theory of squeezing and the nature of quantum noise in optical fields. We examine various atomic sources of squeezed light and discuss phase-sensitive detectors of quantum noise including homodyne and heterodyne detectors. Various successful nonlinear optical methods for generating squeezed light are reviewed. We conclude with a discussion of the possible applications of squeezed light.

ISSN:0950-0340    

DOI:10.1080/09500348714550721

出版商:Taylor & Francis Group    

年代:1987

数据来源: Taylor

摘要:

Quantum-noise reduction to levels nearly 1 dB below the standard quantum limit are reported for light frequencies near an atomic-sodium resonance. This squeezed light is generated in an optical confocal cavity using four-wave mixing due to the atomic-sodium resonance nonlinearity. Squeezed light exits the cavity through a partially reflecting mirror and is detected outside the cavity with a balanced homodyne detector. Experimental details are described for minimizing losses in the atomic beam and detection apparatus. Frequency jitter due to the pump laser also plays a key role in the limits for noise reduction. A wideband phenomenological model is used to analyse the results. Good agreement between this model and the experimental results is obtained. A full quantum model also agrees with the results and predicts even larger squeezing at higher pump intensities. Prospects for achieving this larger-noise-reduction regime are good.

ISSN:0950-0340    

DOI:10.1080/09500348714550731

出版商:Taylor & Francis Group    

年代:1987

数据来源: Taylor

摘要:

The interactions among radiation modes in optical fibres and other Kerr media can create correlations among two, four or more distinct field components. These correlations can reduce the noise levels found with various detector schemes. Some interactions produce the correlations required for quantum non-demolition detection.

ISSN:0950-0340    

DOI:10.1080/09500348714550741

出版商:Taylor & Francis Group    

年代:1987

数据来源: Taylor

摘要:

The possibility of using squeezed states for improving the shot-noise limit of the strain sensitivity of Michelson interferometers is discussed. We find that the spectrum of squeezing required depends on the method of stabilization used in the experiment. Details are given for the widely used phase-modulation technique (which also allows for recycling of the field), where we find an important application for broadband (‘two-mode’) squeezing.

ISSN:0950-0340    

DOI:10.1080/09500348714550751

出版商:Taylor & Francis Group    

年代:1987

数据来源: Taylor

摘要:

Two novel methods of generating light with sub-Poissonian photon-counting statistics are described. Both methods are based on the use of parametric downconversion to generate two beams with simultaneously produced photons. By detecting the photons in one beam a knowledge of the time sequence of the photons in the other beam is obtained and used to modify the initially Poisson statistics. Expressions for the probability distribution functions of the two methods are derived and Fano factors are evaluated.

ISSN:0950-0340    

DOI:10.1080/09500348714550761

出版商:Taylor & Francis Group    

年代:1987

数据来源: Taylor

摘要:

Fluorescence from a coherently driven two-level atom that is damped by a squeezed vacuum is studied. We show that the mean atomic polarization depends on the relative phases of the squeezed vacuum and the coherent driving field. The fluorescent spectrum is calculated and shows several modifications over the spectrum for normal resonance fluorescence. In particular, the central peak of the Mollow triplet has a linewidth that depends on the phase of the driving field. For strong squeezing this peak can either be much narrower or much broader than the natural linewidth of the atom.

ISSN:0950-0340    

DOI:10.1080/09500348714550771

出版商:Taylor & Francis Group    

年代:1987

数据来源: Taylor

摘要:

We discuss the connection between quantum correlations and squeezing in simple quantum optical systems. We illustrate this connection by a study of two-mode states of light produced by parametric down-conversion and similar two-photon processes. The intermode correlations in these systems are shown to be responsible for modifications in photon-number sum and difference operators, and for squeezing in the superpositions of the two modes. The disappearance of the diagonal coherent-state quasiprobability functionP(α) when non-classical light properties are important is noted, and alternative and better-behaved Wigner functions and coherent-state expectationQ-functions for the two-mode system are developed.

ISSN:0950-0340    

DOI:10.1080/09500348714550781

出版商:Taylor & Francis Group    

年代:1987

数据来源: Taylor

摘要:

Various authors have shown that for a particular type of atomic light amplifier, which can be identified as an unsqueezed amplifier, squeezing in the output is destroyed for gains greater than 2, and if the input is classical light then there are no non-classical effects (squeezing or sub-Poisson photon statistics) in the output for any value of the gain; however, these results are not necessarily true for a squeezed amplifier. Here we investigate single-stage and multi-stage squeezed atomic light amplifiers and show that the above non-classical effects can occur even with a coherent-state input. We find that the output of a multistage squeezed amplifier can be squeezed in principle for any desired gain, and that when this amplifier is used as an attenuator, output light can in principle be produced with any desired amount of squeezing for any input.

ISSN:0950-0340    

DOI:10.1080/09500348714550791

出版商:Taylor & Francis Group    

年代:1987

数据来源: Taylor

摘要:

The Hilbert space of a harmonic oscillator with frequency ω can be spanned by the overcomplete set of coherent states of a second oscillator with frequency ω'. These states are squeezed states of the first oscillator. We examine the possibility of generating squeezed states out of coherent states by external changes of the oscillator frequency and explore the two limiting cases of an adiabatic and a sudden change. Only the latter results in squeezing, while in the former symmetrical uncertainities in coordinate and momentum turn out to be adiabatic invariants.

ISSN:0950-0340    

DOI:10.1080/09500348714550801

出版商:Taylor & Francis Group    

年代:1987

数据来源: Taylor