Magneto‐anisotropy of spin dephasing in a [001]‐grown high‐mobility two‐dimensional electron system

The spin dynamics in [001]‐grown two‐dimensional electron systems (2DES) at low temperatures are governed by the effective spin‐orbit fields, which lead to dephasing via the D’yakonov‐Perel mechanism. If both the Rashba and the Dresselhaus spin‐orbit fields are present and of the same order, their interference causes a large anisotropy of the spin dephasing times for spin orientation along different in‐plane directions. This may be observed in time‐resolved Faraday rotation measurements using in‐plane magnetic fields. The dephasing anisotropy is strongly reduced for increasing carrier density by the increasing importance of the kubic Dresselhaus term.