Onset of anisotropic transport of two-dimensional electrons in high Landau levels: Possible isotropic-to-nematic liquid-crystal phase transition

The recently discovered anisotropy of the longitudinal resistance of two-dimensional electrons near half filling of high Landau levels is found to persist to much higher temperatures T when a large in-plane magnetic field B-parallel to is applied. Under these conditions we find that the longitudinal resistivity scales quasilinearly with B-parallel to/T. These observations support the notion that the onset of anisotropy at B-parallel to=0 does not reflect the spontaneous development of charge density modulations but may instead signal an isotropic-to-nematic liquid-crystal phase transition.