弹性应变工程

Elastic strain engineering (ESE) aims to utilize tensile, compressive and deviatoric shear stresses to control the physical and chemical properties of materials. It is broader than high-pressure physics, which deals with hydrostatic, compressive stress only. Since the 1950s, researchers have found that elastic strain and stress can greatly enhance the carrier mobility in semiconductors, and have utilized this in the CMOS industry since the 1990s. With the proliferation of nanomaterials that can survive large stresses (often at 10~100 times their bulk strength), ESE is receiving even more interest in recent years. For example, one may change the bandgap and even the band topology of semiconductors with stress, turning indirect-bandgap material into direct-bandgap material; one may drive exciton motion with an elastic strain gradient, which creates a bandgap gradient; one may change the surface catalytic properties with strain, etc. This article gives a brief overview of the field, and provides key references for prospective researchers.