The introduction of quantum electronic structures for MEMS devices

Abstract

Micro-electro-mechanical structures, MEMS, are now developed with a number of electronic components such as filters and impedance matching circuits, or even whole circuits such a amplifiers and analogue– digital transformers, since the use of a membrane reduces the losses and thus increases the quality factors as required for closely packed multi-channel communication systems [1]. It is notable that there are a number of electronic MEMS circuits where various quantum electronic structures can be usefully incorporated. A typical example is the use of a quantum cascade structure for charge transit effects, such as employed for IMPATT oscillators, or for the recently proposed charge swing for harmonic extraction [2]. In such cases the charge is transferred via a quantum cascade of a series of 2DEG electronic resonators (see Fig. 1) as has been originally introduced for quantum cascade lasers [3]. By bending a MEMS bridge or cantilever, which carries such a succession of quantum resonance structures, it is possible to change the width of the heterostructure resonance valley so that the electronic resonance state occurs at a slightly different energy level. This enables one to affect the electronic charge transfer so that either the current amplitude or the charge transfer time