| In the recent years, optical microcavities have received considerable attention as integrated devices for the future applications in optical sensing, computing and communication. In the area of nonlinear optics, the sub-coherence-length microcavity can also be used to compensate for the phase mismatching, and thus greatly increase the efficiency of the nonlinear frequency conversion. This concept of "cavity phase matching"(CPM) was first proposed by Bloembergen et al. in1962, and induced some theoretical discussions after that. In this thesis we present the first experimental demonstration of CPM, and the realization of several sheet optical parametric oscillators (SOPO) for different applications. They have shown some unique features and advantages for the optical nonlinear frequency conversion, and the study has been extended to the area of quantum optics as well. The main results are listed as follows:1. We first briefly introduced the CPM nonlinear parametric process, and studied oscillation features of SOPO devices in theory. Compared to other phase matching methods, CPM features in high efficiency, high power and broad applicability for intergraded devices.2. We developed an SOPO using KTP crystal and realized type Ⅱ CPM nonlinear process for the first time. Tunable near-frequency-degenerate parametric outputs presented single-longitudinal-mode (SLM), narrow linewidth oscillation. The peak output power reached220kW and the slope efficiency was23.8%. 3. We developed the SOPOs using type-I CPM based on Lithium Niobate crystal. Frequency comb output was obtained near degenerate point, with spectral bandwidth of over50nm and slope efficiency of22.6%. In the highly nondegenerate case, tunable SLM twin beams could be obtained at around850nm and1400nm, which corresponded to the typical line of cesium and telecommunication band. The sloped efficiency was measured to be29.4%. We also predicted SOPO using type0CPM, where SLM mid-infrared output can be expected with ultra-broadband tuning range.4. Based on the study on classical nonlinear optical effects of SOPO, we further studied the corresponding spontaneous processes. The results showed that CPM could also modulate the spectrum of the output nonclassical light, where narrow linewidth or frequency comb spectrum could be obtained. We also theoretically studied the correlation effects for these nonclassical optical fields.5. We proposed the generation of frequency-uncorrelated polarization-entangled two-photon state based on SOPO using BBO crystal. Because the participation of CPM, this two-photon state showed high purity and brightness for both transverse and longitudinal modes. With ultra-fast laser pump, it might be used to realize high visibility multi-photon interference and generate multi-particle non-classical states for quantum information.6. In the end, we extended the study for the correlation effect of light field to the case of stimulated parametric down conversion. The theoretical calculation showed clear temporal correlation even under the high-gain case. This kind of correlation is different from those of spontaneous parametric down conversion or thermal light. Although the correlation showed lower visibility than the spontaneous case, it is less fragile and thus more feasible for practical applications. It may be used for future correlation imaging, lithography and precise clock synchronization. |
PDF Full Text Request