The use of bandgap engineering techniques to tailor the perpendicular transport characteristics of layered semiconductor structures has resulted in a variety of new phenomena and devices concepts. In particular the coherent interaction of electron waves reflected at interfaces gives rise to resonant tunneling effects which filter electrons of certain energy through the structure. A structure specifically designed for electron energy filtering is the variably spaced superlattice energy filter VSSEF in which the quantized states in adjacent quantum wells become aligned under appropriate bias conditions.
This article is from 'Organization of the Optical Society of America Photonic Science Topical Meeting Series. Volume 7. Quantum Optoelectronics Held in Salt Lake City, Utah on 11-13 March 1991,' AD-A253 823, p256-259.