非线性光学量子计算中的互相位调制研究

发布时间：2018-02-17 08:56

本文关键词： 非线性光学量子计算克尔非线性互相位调制　出处：《山东大学》2012年硕士论文　论文类型：学位论文

【摘要】：量子计算科学是现代量子物理最重要的应用之一。在量子计算中,量子相干和量子纠缠已经被证明可以加快某些特定问题的计算速度,比如,在密码学领域中打破RSA标准,或者由建立简单的计算设备比如模拟机,特定程序的计算器等。量子光学计算包括线性光学量子计算(LOQC)和非线性光学量子计算(NLOQC),而光子作为光学量子计算的量子比特,由于其自身稳定性,被认为是合适的量子信息传递的备选载体。基于克尔非线性(Kerr Nonlinearity)的互相位调制(XPM)是一些量子逻辑门的物理基础,比如CNOT逻辑门,因此互相位调制对于非线性光学量子计算是非常关键的。目前,对互相位调制的研究从连续场驱动,强耦合,半经典动力学向脉冲泵浦的,少光子量级的和全量子化的模型发展。电磁诱导透明(EIT)已经被证明在产生巨克尔非线性效应上是有效的,尤其是双电磁诱导透明机制。然而,最近有研究指出基于电磁诱导透明的互相位调制在产生了巨互相位调制的同时不能产生高保真度的逻辑门。在这篇论文中,我们详细研究了这个问题。特别地,我们指出了在量子计算中,对于有效的互相位调制逻辑门有四个评判标准。第一个评判标准是巨非线性,对于这一点,电磁诱导透明是个很好的机制。第二个评判标准是互相位调制应该基于单光子量级或少光子量级,因为在量子计算中,一般单光子是作为量子比特出现的。第三个评判标准是脉冲传播时间的一致性,这个条件可以由双电磁诱导透明满足。最后一个评判标准是输入输出的保真度足够高,然而在目前没有有效的机制满足这个条件。进一步,针对高保真和互相位调制间的矛盾,我们探讨了自发辐射诱导相干(SGC)在互相位调制中的效应,我们发现自发辐射诱导相干是一个很有效的机制,对构建量子逻辑门有一定的发展潜力。
[Abstract]:Quantum computing science is one of the most important applications of modern quantum physics. In quantum computation, quantum coherence and quantum entanglement has proven the calculation speed, can speed up certain problems such as breaking the RSA standard in the field of cryptography, or by the establishment of simple computing devices such as simulation machine, specific program calculator. Quantum optics the calculation includes the linear optical quantum computing (LOQC) and nonlinear optical quantum computing (NLOQC), and the photon as the optical quantum computing quantum bits, because of its stability, is considered to be the candidate for quantum information carriers.
Based on the nonlinear Kerr (Kerr Nonlinearity) of the cross phase modulation (XPM) is the physical basis of some quantum logic gates, such as CNOT logic gates, so the cross phase modulation in nonlinear optical quantum computing is very important. At present, the research on cross phase modulation in continuous driving field, strong coupling, semi classical dynamics to pulse pump the few photon level and fully quantized models. The electromagnetically induced transparency (EIT) has been shown to produce in the giant Kerr nonlinear effect is effective, especially double electromagnetically induced transparency mechanism. However, recent studies have pointed out that the cross phase modulation based on electromagnetically induced transparency in a huge cross phase modulation at the same time can not produce high fidelity gate. In this thesis, we have studied this problem. In particular, we pointed out that in quantum computing, the XPM logic effectively The door has four criteria. The first criterion is a giant nonlinear, for this, electromagnetically induced transparency is a good mechanism. The second criteria is the cross phase modulation of single photon level or less should be based on the photon level, because in quantum computation, single photon is used as quantum bits. The third criterion is the consistency of the pulse propagation time, this condition can be satisfied by double EIT. Finally an evaluation standard is the input and output of high fidelity, but at present there is no effective mechanism to meet this condition. Further, to solve the contradiction between high fidelity and cross phase modulation, we investigate the spontaneous radiation induced coherence (SGC) effect on cross phase modulation in, we found that spontaneously induced coherence is a very effective mechanism has a certain potential for the construction of quantum logic gates.

【学位授予单位】：山东大学
【学位级别】：硕士
【学位授予年份】：2012
【分类号】：O431.2;TP38

【共引文献】