An improvement in a method of controlling lasing in a semiconductor laser fabricated in a photonic crystal laser having a plurality of holes into which a birefringent material with low refractive losses and low optical loses with controllable spatial refractive index orientation has been infiltrated comprises the step of rotating the molecular orientation or changing the physical orientation of the birefringent material infiltrated into the holes of the photonic crystal laser to switch cavity modes. The liquid crystal is aligned by use of an alignable photo addressable polymer layer adjacent to the liquid crystal. The cavity modes are optically switched within the laser without any requirement of external energy to maintain the lasing state of the laser, which allows its use as a memory element.