Quantum langevin equation method in non-Markovian dynamics

非马尔可夫动力学中的量子朗之万方程方法

基本信息

批准号：
17F17821
负责人：
NORI FRANCO
金额：
$ 1.41万
依托单位：
Institute of Physical and Chemical Research
依托单位国家：
日本
项目类别：
Grant-in-Aid for JSPS Fellows
财政年份：
2017
资助国家：
日本
起止时间：
2017-11-10 至 2020-03-31
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-17F17821/
关键词：
open quantum systems bath information harmonic oscillators thermal equilibrium nonlinear coupling two-level system wave approximation

项目摘要

In FY2019, I mainly studied the possibility of generating states with strong quantum properties in coherent Ising machine.Such devices can simulate many-body systems with quantum annealing method. However, the output states of such devices are usually classical, and there is no entanglement in the states during evolution. This limitation prevents the application to general quantum information problems. To solve this disadvantage, we study the way to generate states with strong quantum properties in these machines.We chose the entangled cat state as the target state based on three reasons. First, this state has strong quantum properties because there are both entanglement and coherent superposition in it. Second, the steady state of Ising machine can be a cat states in fine cavity limit, so that it will be more convenient to generate entanglement base on these states. Third, the detection of coherence and entanglement in an entangled cat state is easy due to its macroscopic property.Our current research has made the cat state generation clear, and now is focused on the conversion to the entangled cat state. Before generating entangled cat states, high quality cat states are necessary. Therefore, we studied the condition for cat state generating when dissipation exists. Based on the optimal parameter regimes for cat states, our research is trying to find an efficient way to achieving entangled cat states.

2019财年，我主要研究了在相干伊辛机中产生具有强量子特性的态的可能性。此类设备可以用量子退火方法模拟多体系统。然而，此类设备的输出状态通常是经典的，并且在演化过程中不存在状态纠缠。这种限制阻碍了对一般量子信息问题的应用。为了解决这个缺点，我们研究了在这些机器中生成具有强量子特性的态的方法。基于三个原因，我们选择纠缠猫态作为目标态。首先，这种态具有很强的量子特性，因为它同时存在纠缠和相干叠加。其次，伊辛机的稳态可以是细腔极限内的猫态，这样基于这些状态更容易产生纠缠。第三，由于纠缠猫态的宏观特性，相干性和纠缠的检测很容易。我们目前的研究已经明确了猫态的生成，现在的重点是向纠缠猫态的转换。在生成纠缠猫态之前，高质量的猫态是必要的。因此，我们研究了耗散存在时猫态产生的条件。基于猫状态的最佳参数机制，我们的研究试图找到一种实现纠缠猫状态的有效方法。