Feasibility Study of a Quantum Field-Effect Directional Coupler

在这个方案中，首席研究员将研究量子场效应定向耦合器(QFED)的可行性。QFED是一种旨在利用限制在非常小的半导体结构中的电子的波动性质的装置。QFED基本上由两个平行的电子波导组成，在一定的长度(相互作用长度)上足够紧密地间隔，以便电子可以通过量子力学隧道从一个波导转移到另一个波导。在QFED中，当电子波包沿耦合器向下传播时，电子在两个波导之间交替传输。对于一个耦合器，要将任意给定部分的电子从一个波导传输到另一个，可以控制波导之间的耦合，而不会改变它们的相互作用长度。这是通过穿过耦合器中间的金属栅极的场效应作用来实现的。QFED的作用类似于电流开关，很像一个完整的发射极耦合逻辑门。

In this proposal the principal investigator will study the feasibility of a Quantum Field-Effect Directional Coupler (QFED). The QFED is a proposed device that intends to exploit the wave nature of electrons confined to a very small semiconductor structures. The QFED consists basically of two parallel electron waveguides sufficiently closely spaced over a certain length (the interaction length) so that electrons can be transferred from one waveguide to the other by quantum mechanical tunneling. In a QFED, electrons transfer alternatively between the two waveguides as the electron wave packet travels down the coupler. For a coupler to transfer any given fraction of the electrons from one waveguide to the other, coupling between the waveguides can be controlled without changing their interaction length. This is achieved by the field-effect action of a metal gate running through the middle of the coupler. The QFED behaves as a current switch, much like an entire Emitter-Coupler Logic gate.