Spatial Squeezing, Entanglement, and Solitonic EPR Sources in Chi(2) Minicavities

该奖项旨在支持光学二次谐波产生中的空间压缩研究。在20世纪80年代和90年代，人们开发出了表现出时域正交压缩、双光束相关和其他量子光学现象的辐射场的实用源。我们将研究由光学二次谐波产生的非经典光的空间方面。理论上预言，空间压缩作为横向调制不稳定性的亚临界前兆出现在二次谐波产生中。我们正在进行一系列实验，旨在观察调制不稳定性阈值以上的经典模式，以及阈值以下的量子签名。 实验工作采用单谐振腔和双谐振腔，由连续波和纳秒脉冲近红外光源驱动。详细的测量将作为腔调谐，相位失配和空间波数的函数的压缩程度。我们也将工作与参数制度的二次谐波场，是内部产生的光学腔直接驱动的光学参量振荡的竞争过程。这种所谓的内部泵浦光参量振荡器（IPOPO）具有独特的特点，即利用单个非线性晶体在与入射泵浦光相同的波长处产生显示非经典相关的下转换参量场。这消除了对单独的倍频级的需要，这降低了器件的复杂性，并且极大地促进了组合工艺的频率调谐。由此产生的正交压缩场将用于测量亚散粒噪声分辨率的空间位移。与实验工作并行的是，我们将对不同可能的腔结构进行空间压缩谱的理论计算。特别是搜索将在IPOPO设备中的空间调制场提供连续变量纠缠的参数制度。该项目的教育部分将包括培训研究生掌握现代实验和理论技术，使非经典光场的应用成为可能。

This award is in support of studies of spatial squeezing in optical second harmonic generation. Practical sources of radiation fields exhibiting time domain quadrature squeezing, twin-beam correlations, and other quantum optical phenomena were developed in the 1980's and 1990's. We will investigate spatial aspects of non-classical light generated by optical second harmonic generation. Spatial squeezing has been theoretically predicted to appear in second harmonic generation as a sub-critical precursor of transverse modulational instability. We are working on a series of experiments aimed at observing both classical patterns above the modulational instability threshold, as well as the below threshold quantum signatures. The experimental work uses singly and doubly resonant optical cavities driven by continuous wave and nanosecond pulsed near infrared sources. Detailed measurements will be made of the degree of squeezing as a function of cavity tuning, phase mismatch, and spatial wavenumber. We will also work with parameter regimes where the second harmonic field that is internally generated in the optical cavity directly drives the competing process of optical parametric oscillation. This so-called internally pumped optical parametric oscillator (IPOPO) has the unique feature that the down converted parametric fields that display non-classical correlations are generated at the same wavelength as the incident pump beam using a single nonlinear crystal. This eliminates the need for separate frequency doubling stages, which reduces device complexity, and greatly facilitates frequency tuning of the combined process. The resulting quadrature squeezed fields will be used for measurements of spatial displacement with sub shot-noise resolution.In parallel with the experimental work we will perform theoretical calculations of the spectrum of spatial squeezing for the different possible cavity configurations. In particular a search will be made for parameter regimes that provide continuous variable entanglement of spatially modulated fields in the IPOPO device. The educational component of the project will include training graduate students in modern experimental and theoretical techniques that enable applications of non-classical light fields.