Effect of a tilted magnetic field on the orientation of Wigner crystals

Abstract

We study the effect of a tilted magnetic field on the orientation of Wigner crystals by taking account of the width of a quantum well in the $z$-direction. It is found that the cohesive energy of the electronic crystal is always lower for the $[110]$ direction parallel to the in-plane field. In a realistic sample, a domain structure forms in the electronic solid and each domain orients randomly when the magnetic field is normal to the quantum well. As the field is tilted an angle, the electronic crystal favors to align along a preferred direction which is determined by the in-plane magnetic field. The orientation stabilization is strengthened for wider quantum wells as well as for larger tilted angles. Possible consequence of the tilted field on the transport property in the electronic solid is discussed.