Electric Field Effect on Weak Localization in a Semiconductor Quantum Wire

The inf luence of an e lec t r i c f i e l d on weak loca l i za t ion in a semiconductor quantum wire is studied by a recently proposed generalized quantum Langevin equation approach to the conduct iv i ty problem. A new physical p icture is presented. In our model the e lect ronic motion is essent ia l ly one-dimensional, and the phase coherence length I¢ is much larger than the e las t i c mean free path % of e lectrons. We f ind that when the e lec t r i c f i e l d E exceeds a c r i t i c a l value E c = 2 where is HVF/e~ $ , V F the Fermi velocity, introduce a new cut-off length L s = (Ec/EJ~x $ i t wi l l with implications for the experimental results on semiconductor quantum wires. Our theory is in good agreement with the experiments of Hiramoto and co-workers.