Optical electron-hole tweezers in semiconductors

The theory of transversal light forces on electron-hole pairs in semiconductors has been formulated recently (Lindberg and Binder 2003 J. Phys.: Condens. Matter 15 1119), but only light forces from single Gaussian beams were considered. In the present paper, it is shown theoretically that Hermite-Gaussian beams can be used to reduce and even reverse natural wavepacket spreading. Furthermore, a spatially moving beam can be used to displace and accelerate an electron-hole plasma, in analogy to well-known optical tweezers in atomic systems. The light forces exerted by Hermite-Gaussian beams appear to be robust and therefore of possible practical importance.