Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Log inSign up
Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Blog
Job Board
Q3AS

© 2026 Aqora Quantum S.A.S.

TermsPrivacyLegal Notice

Physical Review A

Conversion of random-phase light into phase-coherent light

Hari Prakash, Naresh Chandra, Vachaspati

Published May 1, 1974• 13 citations
Publisher

Abstract

It is shown that light having completely random phase can be converted into phase-coherent light (having fixed values of phase) by parametric amplification with an intense coherent second-harmonic pump mode. Explicit results for a chaotic signal and experimental detection of interference between phase-coherent beams obtained from independent random-phase light beams is discussed.

DOI
10.1103/physreva.9.2167

Related papers

Comment on "Conversion of random-phase light into phase-coherent light"

Maurice T. Raiford

Previous results concerning the evolution of the signal towards light of well-defined phase during the degenerate parametric amplification process are pointed out, as well as how this is affected by damping, the time dependence of the pump, and the additional process of frequency up-conversion.

Physical Review A•May 1, 1975•0 citations

Coherence in two-photon down-conversion induced by a laser

L. J. Wang, X. Y. Zou, L. Mandeļ

Normally, the signal and idler photons produced in the process of parametric down- conversion exhibit no second-order interference. However, in the presence of an external laser beam that follows the path of the signal photon and induces stimulated down-conversions, one would expect coherence to develop between the down-converted signal and idler beams. We have demonstrated the existence of this phenomenon in an experiment with two down-converters pumped by similar pump beams, in which two mutually coherent laser beams followed the paths of the two down-converted signal photons and induced coherence between the two down- converted idler beams. The induced coherence gives rise to observable interference effects, which are presented.

Annual Meeting Optical Society of America•Jan 1, 1990•1 citation

Detection of phase-modulated optical signals through two-wave mixing in photorefractive materials

L. Boutsikaris, Fred Davidson

Two-wave mixing in photorefractive crystals has been shown to combine coherently a modulated optical signal beam with a strong pump optical field.’ For a phase-modulated signal beam, the induced index of refraction phase grating inside the crystal yields a coupling of the optical fields of the pump and signal so that subsequent intensity detection results in apparent intensity modulation of the transmitted signal or pump beams. This provides an easy way to detect phase differences between two optical beams. Some of the advantages the above scheme offers over commonly used coherent optical phase detection schemes are: no loss of 3 dB in the signal beam intensity at the 50/50 beam splitter (used to combine signal and local oscillator fields); automatic alignment of the index of refraction grating with the two incident optical wavefronts; insensitivity to slow random changes in the phases of both beams. Experimental results are given, and a new definition for the resulting mixing gain for the phase-modulated beam is introduced, through which optimal conditions for input beam intensity ratios can be found. Applications to coherent homodyne detection are discussed.

Annual Meeting Optical Society of America•Jan 1, 1988•0 citations

Second-harmonic generation by a partially coherent beam

Muhammad Suhail Zubairy, John K. McIver

The effect of degradation of the coherence of the pump beam by a random phase screen on the conversion efficiency in the second-harmonic generation process is considered. It is shown that, under suitable conditions, the conversion efficiency can be increased significantly.

Physical Review A•Jul 1, 1987•35 citations

Coherent optical detection through two-wave mixing in photorefractive materials

F. Davidson, Michael A. Krainak, L. Boutsikaris

Photorefractively induced index-of-refraction phase gratings are shown to combine coherently the optical fields of a strong pump and a suitably amplitude- or phase-modulated signal beam in such a way that an apparent amplification of the modulating waveform appears as intensity modulation of the transmitted signal and pump beam intensities. The source of the signal gain is shown to be the square-law (intensity) detection of the coherently combined pump and modulated signal beams, just as in coherent optical communication systems in which a strong local-oscillator field is coherently added with a weak optical signal field by a beam splitter.

Optics Letters•Jun 1, 1988•22 citations

Probing the two-photon phase coherence of parametrically down-converted photons by a local oscillator

Masato Koashi, K. Kono, Masaya Matsuoka +1 more

A degenerate beam of down-converted photon pairs from a nonlinear crystal pumped by pulsed light was mixed with coherent local oscillator pulses by a beam splitter, and the coincidence rate for detections of photons at the two output beams was measured. The coincidence rate showed interference fringes as the phase difference between the pump light and the local oscillator was varied. It showed a negative correlation in some range of the phase difference.

Physical Review A•Nov 1, 1994•16 citations
It is shown that light having completely random phase can be converted into phase-coherent light (having fixed values of phase) by parametric amplification with an intense coherent second-harmonic pump mode. Explicit results for a chaotic signal and experimental detection of interference between phase-coherent beams obtained from independent random-phase light beams is discussed.
Normally, the signal and idler photons produced in the process of parametric down- conversion exhibit no second-order interference. However, in the presence of an external laser beam that follows the path of the signal photon and induces stimulated down-conversions, one would expect coherence to develop between the down-converted signal and idler beams. We have demonstrated the existence of this phenomenon in an experiment with two down-converters pumped by similar pump beams, in which two mutually coherent laser beams followed the paths of the two down-converted signal photons and induced coherence between the two down- converted idler beams. The induced coherence gives rise to observable interference effects, which are presented.
Two-wave mixing in photorefractive crystals has been shown to combine coherently a modulated optical signal beam with a strong pump optical field.’ For a phase-modulated signal beam, the induced index of refraction phase grating inside the crystal yields a coupling of the optical fields of the pump and signal so that subsequent intensity detection results in apparent intensity modulation of the transmitted signal or pump beams. This provides an easy way to detect phase differences between two optical beams. Some of the advantages the above scheme offers over commonly used coherent optical phase detection schemes are: no loss of 3 dB in the signal beam intensity at the 50/50 beam splitter (used to combine signal and local oscillator fields); automatic alignment of the index of refraction grating with the two incident optical wavefronts; insensitivity to slow random changes in the phases of both beams. Experimental results are given, and a new definition for the resulting mixing gain for the phase-modulated beam is introduced, through which optimal conditions for input beam intensity ratios can be found. Applications to coherent homodyne detection are discussed.
Photorefractively induced index-of-refraction phase gratings are shown to combine coherently the optical fields of a strong pump and a suitably amplitude- or phase-modulated signal beam in such a way that an apparent amplification of the modulating waveform appears as intensity modulation of the transmitted signal and pump beam intensities. The source of the signal gain is shown to be the square-law (intensity) detection of the coherently combined pump and modulated signal beams, just as in coherent optical communication systems in which a strong local-oscillator field is coherently added with a weak optical signal field by a beam splitter.