QUANTUM DEVICES WITH MULTIPOLE-ELECTRODE — HETEROJUNCTIONS HYBRID STRUCTURES

Since the introduction of the man-made superlattices and quantum well structures, the field has taken off and developed into Quantum Slab, QS; Quantum Wire, QW; Quantum Dot, QD; and Nanoelectronics. This rapidly expanding field owes its success to the development of epitaxially grown heterojunctions and heterostructures to confine carriers in injection lasers. Meanwhile, the advancement of lithography allows potentials to be applied in nanoscale dimension leading to the possibility of quantum confinement without heterostructures. Actually, quantum states in the inversion layer of field effect transistors, FETs, formed by the application of a large gate voltage appeared several years before the introduction of the superlattices and quantum wells. The quantum Hall effect was first discovered in the Si inversion layer. This chapter, Multipole-Electrode Heterojunction Hybrid Structure, MEHHS, discusses hybrid structures of heterojunctions and applied potentials via multipole-electrodes for a much wider variety of structures for future quantum devices. The technology required to fabricate these electrodes, to some degree, is routinely used in the double-gate devices. Few specific examples are detailed here, hopefully, to stimulate a rapid adoption of a hybrid system for the formation of quasi-discrete states for quantum devices.