从多光子干涉到玻色采样的实验研究

发布时间：2018-01-24 09:12

本文关键词： 多光子干涉 GHZ定理量子精密测量玻色采样　出处：《中国科学技术大学》2017年博士论文　论文类型：学位论文

【摘要】：本论文主要内容是基于多光子干涉的若干问题的实验研究。多光子干涉是一种纯碎的量子效应,其应用范围极其广泛,包括量子力学基础检验、量子精密测量、量子计算和量子模拟等等。在量子力学基础检验方面,GHZ定理以一种"非此即彼"的方式直接证否EPR实在元素的概念。2000年,人们首次实验验证了三粒子的GHZ定理。随后十几年间,GHZ定理不断地被推广到更多粒子的情形。然而,所有这些后续的实验都可以约化到三粒子的情形。通过关闭这个可约化漏洞,我们首次实验检验了真正超越三粒子纠缠的GHZ定理。在量子精密测量方面,人们发现多光子纠缠态可用来超越经典测量技术的散粒噪声极限。然而,多光子纠缠态的制备和探测往往依赖于后选择技术或低效率的非线性性。这严重影响了多光子纠缠在量子精密测量上的应用。通过偏振模式和路径模式的混合编码,我们简化了量子傅里叶变换干涉仪的搭建。在此基础上,我们确定性地观察到了最多四个光子的超分辨现象。在量子计算和量子模拟方面,玻色采样是多光子干涉的一个新的研究热点,是近期最有可能展现出超越经典电脑运算能力的模型之一。我们实验研究了两种不同单光子源的玻色采样:基于参量下转换的概率性单光子源,以及量子点确定性单光子源。前者可通过增加单光子源的数量并随机化输入的方式克服多光子亮度指数衰减难题,但是多对噪声问题依然制约着参量光源在玻色采样上的扩展,我们系统研究了这个问题并提出解决方法。后者原则上不存在多对噪声问题。最近,我们组在同一个量子点上同时实现了高亮度、高不可分辨性和高单光子性三个关键性指标。在此基础上,我们搭建了基于量子点单光子源的时间编码的可编程的玻色采样实验平台,首次把玻色采样的光子数推进到了四个,为实现真正超越经典电脑运算能力的玻色采样打下了坚实的基础。
[Abstract]:The main content of this thesis is based on the experimental study of several problems of multiphoton interference. Multiphoton interference is a pure broken quantum effect, which is widely used, including quantum mechanics basic test, quantum precision measurement. Quantum Computation and Quantum Simulation, etc. In terms of fundamental testing of quantum mechanics, the GHz theorem directly proves the concept of EPR real elements in a "either / or" manner. 2000. For the first time, the three-particle GHZ theorem has been experimentally verified. For more than a decade, the GHz theorem has been extended to the case of more particles. All these subsequent experiments can be reduced to the case of three particles. By closing this reducible loophole, we have for the first time tested the GHZ theorem, which really transcends the entanglement of three particles, in terms of quantum precision measurement. It has been found that the multiphoton entangled state can be used to exceed the particle noise limit of classical measurement techniques. The preparation and detection of multi-photon entangled states often depend on the post-selection technique or the inefficiency of nonlinearity, which seriously affects the application of multi-photon entanglement in quantum precision measurement. Code. We have simplified the construction of quantum Fourier transform interferometer. On this basis, we have observed the superresolution of up to four photons with certainty in quantum computation and quantum simulation. Boson sampling is a new research hotspot in multiphoton interference. It is one of the most likely models to outperform the classical computer computing power in the near future. We have experimentally studied two kinds of Bose sampling of single photon sources: probabilistic single photon sources based on parametric downconversion. The former can overcome the problem of multi-photon luminance exponent attenuation by increasing the number of single-photon sources and randomizing the input. However, the problem of multi-pair noise still restricts the expansion of parametric light source on boson sampling. We have systematically studied this problem and put forward a solution. The latter, in principle, does not have the problem of multi-pair noise. Recently. Our group has realized three key indexes of high brightness, high indiscernibility and high single photon property simultaneously on the same quantum dot. We set up a programmable Bose sampling experimental platform based on time coding of quantum dot single photon source and advanced the number of boson sampling to four for the first time. It lays a solid foundation for the realization of Bose sampling, which surpasses the classical computing ability.
【学位授予单位】：中国科学技术大学
【学位级别】：博士
【学位授予年份】：2017
【分类号】：O431.2

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