The technological advancement of data storage is reliant upon the continuous development of faster and denser memory with low power consumption. Recent progress in flash memory has focused on increasing the number of bits per cell to increase information density. In this work an optical multilevel spin bit, based on the chiral induced spin selectivity (CISS) effect, is developed using nanometer sized chiral quantum dots. A double quantum dot architecture is adsorbed on the active area of a Ni based Hall sensor and a nine-state readout is achieved.

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A Nd:YAG laser crystal was pumped at 946 nm and lased at 1064 nm. This pump-lase format was investigated in order to reduce the quantum defect between the pump and laser photons as compared to other pump schemes of this material. To the best of our knowledge, this is the first realization of this scheme. A room temperature absorption coefficient and linewidth of approximately 0.075 cm(-1) and approximately 1 nm for 1% at. Nd(+3) concentrations were measured for the 946 nm absorption line. Those parameters impose both narrow-bandwidth pumping and a long absorption path. By increasing the laser crystal temperature above room temperature, the absorption cross sections at 946 and 938 nm increase due to enhanced thermal population of the upper energy level of the ground manifold. The possibility of exploiting this phenomenon to enhance the pump absorption is also discussed.