Fabry-Perot(FP) Microcavity And Its Application

The work of this paper mainly focuses on the research of FP microcavity.Based on the longitudinal modulation of FP microcavity,the fineness of FP microcavity is greatly improved,and it is applied to all-solid-state laser technology and nonlinear optics and quantum optics.In the field of optics,laser frequency locking and cavity phase matching are achieved.The modulation of the lateral transmission of the light field is realized by the hybrid linear-nonlinear PT optical medium,which has the advantages of integration and high efficiency.A four-point summary of the paper is as follows:Firstly,laser frequency stabilization was achieved through the use of a high-precision FP microcavity self-injection-locked semiconductor laser.An FP microcavity with a fineness of 137 was independently developed,and a 1550nm distributed feedback(DFB)semiconductor laser was self-injection locked.Due to the frequency traction,the locked laser frequency was determined by the microcavity resonance peak,which effectively suppressed the frequency shift was caused by the fluctuation of the DFB laser’s current.It greatly increased the side mode suppression ratio of the outgoing spectrum and narrowed the laser’s linewidth.Secondly,the optical parametric oscillation of a three-resonance device is achieved via cavity phase matching.A 500 μm x-cut type-II KTP crystal was utilized to create the first three-resonance sheet optical parametric oscillator(SOPO),which uses optical coating to produce the three resonances of pump light,signal light,and idler light.The three-resonance SOPO has many advantages compared to a common double resonance SOPO,including a greatly reduced minimum threshold of 13 μJ and a substantially improved conversion efficiency of 17.5%at temperatures near 65℃.This microcavity can provide many potential benefits to the fields of spectrometry and quantum optics,especially in concurrent applications with lasers of single longitudinal mode and narrow linewidth.Thirdly,cavity phase matching was used to study narrow-band photon-pair generation.It was apparent that when the pump light intensity is much lower than the vibration threshold,a two-photon state with a line width on the order of GHz can be directly generated by the SOPO,allowing for the calculation of frequency degeneracy,non-simplification,and in certain cases double quantum interference.A SOPO tuned for frequencies near the degeneration point of the two-photon states was created using an x-cut type-Ⅱ matched KTP crystal with a cavity length of 217 μm.Near the SOPO’s design wavelength of 1064nm,it has a resonance peak line width of 1.5 GHz and the Q value of 104.It Was found that a tunable Single longitudinal mode optical parametric oscillation can be achieved by using a 532 nm single longitudinal mode laser pump with a conversion efficiency of up to 30%.These results lay the groundwork for conducting future two-photon state characterization experiments.Fourthly,light field localization guidance in the one-dimensional PT-symmetric optical lattice is realized.By combining the nonlinear and PT-symmetric potentials,the localized guidance of the beam during transmission was achieved.The beam can be deflected as necessary by adjusting the nonlinear intensity.