Self-assembled GaAs quantum dashes for direct alignment of liquid crystals on a III–V semiconductor surface

The development of tunable photonic devices is strategic for miniaturized optical instrumentation and sensing systems. Exploiting the birefringence variation of liquid crystals (LCs) instead of MEMS actuation in such devices could bring better spectral stability and lower power consumption. However, aligning LCs inside a III–V semiconductor device is tricky. We demonstrate that self-assembled gallium arsenide (GaAs) quantum dashes (QDHs) could serve as direct planar aligners for LC nematic molecules. The alignment quality and birefringence variation of a LC-microcell embedding QDHs are shown to be similar to those of a polymer nanograting-based reference, with the added advantage of better electrical performance.