【摘 要】
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N onlinear frequency conversion of light involves in-teraction of photons through the nonlinear dielec-tric response of materials to generate light at new frequencies.The first demonstration of nonlinear optical frequency conversion was that of second-har
【机 构】
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Department of Physical Electronics,Faculty of Engineering,Tel-Aviv University,Tel-Aviv 6779801,Israe
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N onlinear frequency conversion of light involves in-teraction of photons through the nonlinear dielec-tric response of materials to generate light at new frequencies.The first demonstration of nonlinear optical frequency conversion was that of second-harmonic gener-ation (SHG) [1].In this process,two input photons at fre-quency ω combine in a material to coherently emit a single photon at frequency 2ω.Since then,many other nonlinear frequency conversion processes have been demonstrated,including different schemes of three and four-wave-mixing as well as higher order interactions [2].
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