Multi-channel router and logic NAND gate from multiple Autler-Townes splitting controlled by phase transition

Abstract

For the first time, we investigated the electric-dipole transition dependent primary and secondary temporal Autler-Townes (TAT)-splitting of a hybrid signal (fluorescence and Stokes) in Pr³⁺:YPO₄. We compared the TAT-splitting in different phases (pure tetragonal (T), pure hexahedral (H), (T + H)-phase, and (H + T)-phase) of the Pr³⁺:YPO₄ crystal. The TAT-splitting in the (H + T)-phase was observed to be stronger than that in other phases, while the Pr³⁺ ion had stronger dressing than the Eu³⁺ ion in the host material of YPO. Furthermore, we observed that the ratio of primary and secondary TAT-splitting can be controlled by the single and double dressing effect using the power and detuning of employed laser fields. In our experiment, we observed that secondary splitting from secondary dressed levels can only be observed at the resonance wavelength in the three-level system. Based on the results, we proposed a model for a multi-channel optical router and logic NAND gate. The routing action results from primary and secondary TAT-splitting, while the NAND gate was realized by the primary dressed states.