Abstract
A new class of band-gap conversion scheme based on proximity effects is described, which allows the otherwise indirect-gap Si to behave more like a neighboring direct-gap semiconductor in terms of radiative transition. Evanescent coupling of the electronic wave function of Si to that of the adjacent direct-gap counterpart in the mid-gap across the interface of staggered band alignment is taken advantage of to exploit the dipoleallowed, momentum-conserving quasi-direct interband recombination. The quasi-direct GaSb-Si quantum dot system created thereby will be reviewed with some of the prominent features being highlighted as represented by near-infrared gain.
