Heat transport in quantum devices

自然界中的许多现象可以用温差引起的能量自发转移来描述。例如，放在杯子里的热咖啡会因为与周围环境的能量交换而逐渐冷却，直到咖啡的温度达到平衡。对量子物体的冷却机制进行建模对于研究影响量子器件(如量子计算机)的耗散过程是至关重要的。该项目的目标是对小型量子设备中的热传输进行建模。这些可以通过连接到几个温度T_i的恒温器的量子比特网络来体现。恒温器的作用将使用所谓的Lindblad主方程来建模，并将探索记忆(非马尔科夫)对能量流的影响。一旦建模阶段完成，下一个目标是研究如何控制和优化网络不同部分之间的能量流动。例如，人们可以通过作用于第三个终端来控制两个恒温器之间的热流，放大、抑制和反转它，从而实现量子热阀或晶体管。计算将通过解析和数值两种方式进行。

Many phenomena in nature can be described by spontaneous transfer of energy due to a temperature difference. For example a warm coffee left in a cup will gradually cool down due to energy exchange with the surroundings until the temperature of the coffee reaches an equilibrium. Modelling the cooling mechanism of quantum objects is pivotal for studying dissipation processes affecting quantum devices, e.g. quantum computers. The objective of the project is to model heat transport in small quantum devices. These could be embodied by a network of qubits connected to several thermostats with a temperature T_i. The action of the thermostats will be modelled using so-called Lindblad master equations and memory (non-Markovian) effects on the energy flow will be explored. Once the modelling stage is completed, the next goal is to investigate how energy flow between different parts of the network can be controlled and optimised. One can, for instance, control the heat flow between two thermostats, amplifying, suppressing and inverting it, by acting on a third terminal thus realising a quantum heat valve or transistor.Calculations will be performed both analytically and numerically.