Abstract
We demonstrate all-optical quantum interference injection and control of a ballistic pure spin current (without an accompanying charge current) in quantum wells, consisting of spin-up electrons traveling in one direction and spin-down electrons traveling in the opposite direction. This current is generated through quantum interference of one- and two-photon absorption of phase-locked pulses that have orthogonal linear polarizations. We use a spatially resolved pump-probe technique to measure carrier movement of . Results agree with recent theoretical predictions.
- Received 19 November 2002
DOI:https://doi.org/10.1103/PhysRevLett.90.136603
©2003 American Physical Society