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Updated: Jun 9, 2026

The Generation of Higher-order Laguerre-Gauss Optical Beams for High-precision Interferometry
Published on: August 12, 2013
Time-delay Fizeau phase-conjugate interferometer
Abstract:
A time-delay Fizeau phase-conjugate interferometer is constructed by using a BaTiO(3) crystal in a degenerate four-wave-mixing configuration. The slow response time of BaTiO(3) is used to build a phase-conjugate mirror that functions as a holographic memory. An optical wave and its time-delayed version are stored inside the crystal sequentially while their phase-conjugate waves are generated simultaneously. Superposition of the two phase-conjugate waves produces an interferogram as a result of the relative phase change of the input waves. The simplicity and real-time operation of this technique lead to several advantages over the conventional holographic interferometry. The use of photorefractive crystal eliminates the darkroom process and reposition procedure. A higher accuracy can be achieved because the interfering waves are phase-conjugate waves. The principle of this technique is presented and the experimental results and its applications are discussed.
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