Coupled quantum-dot devices based on the reaction-diffusion dynamics

在这项工作中，我们提出了一种模拟反应扩散系统动力学的量子点装置。反应扩散系统(RD系统)是化学反应和物质扩散以非平衡态共存的化学系统。自然界中有各种各样的RD系统，各种动态的、自组织的自然现象可以用RD动力学的概念来解释。构建反应扩散系统的电学模拟将使我们能够在LSI芯片上产生人工生物动力学，开发生物启发的信息处理系统。我们提出构建一种电学模拟的RD系统，即由量子点电路组成的电学RD系统。RD系统可以看作是相互作用的化学非线性振子的集合体，因此我们可以用电振子代替化学振子来构建电气RD系统。我们使用由库仑阻塞现象引起的非线性振荡的量子点电路作为电子振荡器。RD系统中的扩散作用可以用振子之间的电容耦合来模拟。通过将耦合振子排列成一个网络，我们设计了一个量子点RD系统。我们通过计算机模拟表明，该系统产生了电耗散结构，即电路中节点电位的动态时空图案，这是一个类似于化学RD系统的特征。

In this work, we proposed a quantum-dot device that imitated the dynamics of reaction-diffusion systems. A reaction-diffusion system (RD system) is a chemical system where chemical reactions and material diffusion coexist in a nonequilibrium state. There are various RD systems in nature, and a variety of dynamic, self-organizing natural phenomena can be explained using the concept of RD dynamics. Constructing an electrical analog of reaction-diffusion systems will enable us to generate artificial biodynamics on a LSI chip and develop bioinspired information-processing systems.We proposed constructing an electrical analog of RD systems, i.e., an electrical RD system consisting of quantum-dot circuits. An RD system can be considered an aggregate of chemical nonlinear oscillators interacting with one another, so we can construct electrical RD systems by using electrical oscillators instead of chemical ones. We used, as the electrical oscillator, a quantum-dot circuit that produced nonlinear oscillation caused by the Coulomb blockade phenomenon. The action of diffusion in RD systems can be imitated by capacitive coupling between the oscillators. By arranging coupled oscillators into a network, we designed a quantum-dot RD system. We showed through computer simulation that the system produced electrical dissipative structures, or animated spatiotemporal patterns of node potential in the circuit, which was a characteristic similar to that in chemical RD systems.