Phase conjugation

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Phase conjugation is a physical transformation of a wave field where the resulting field has a reversed propagation direction but keeps its amplitudes and phases.

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Description

It is distinguished from Time Reversal Signal Processing by the fact that phase conjugation uses a holographic or parametric pumping whereas time reversal records and re-emits the signal using transducers. [1]

Both techniques allow an amplification of the conjugate wave compared to the incident wave. [1]

As in time reversal, the wave re-emitted by a phase conjugation mirror will auto-compensate the phase distortion and auto-focus itself on its initial source, which can be a moving object. [1]

Propagation of a time reversal replica demonstrates a remarkable property of phase-conjugated wave fields. [2] Phase conjugation of wave field means the inversion of linear momentum and angular momentum of light. [3]

Phase conjugation methods exist in two main domains:

See also

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References

  1. 1 2 3 A. P. Brysev et al., Wave phase conjugation of ultrasonic beams, Physics-Uspekhi (1998)
  2. Okulov, A Yu (2008). "Angular momentum of photons and phase conjugation". Journal of Physics B: Atomic, Molecular and Optical Physics. 41 (10): 101001. arXiv: 0801.2675 . Bibcode:2008JPhB...41j1001O. doi:10.1088/0953-4075/41/10/101001. ISSN   0953-4075. S2CID   13307937.
  3. A.Yu. Okulov, "Optical and Sound Helical structures in a Mandelstam-Brillouin mirror". JETP Lett, v.88, n.8, pp. 561-566 (2008)]