11:00 AM - 11:15 AM
▲ [18a-225B-7] Towards Topological Laser Based on Dielectric Photonic Crystals
Keywords:photonic crystal, topological insulator, laser
The photonic topological insulators provide ideal platforms for photonic applications, which always require defect-tolerant properties to reduce losses. However, most photonic topological states work in the microwave frequency band, and require external magnetic field, which hinder their usages in applications.
Wu and Hu proposed a scheme to achieve topological photonic crystals by using dielectric materials. Starting from honeycomb structure, they adjust the locations of pillars and get a pair of topological edge states with opposite orbital angular momenta, which play the role of pseudospin, at the interface between topological and trivial photonic crystals. Because only dielectric materials are used, this scheme can be pushed to the optical frequency band and no external magnetic field is required.
In the present work, as the cavity for lasing, we construct the topological interface states achieved in the above scheme. We can write the equation of motion in a tight binding picture. By adjusting the real-valued hopping coefficients in the equation, we can design topological and trivial photonic crystals, between which there yield topological interface states.
By numerical solving the above equation, we successfully observe a pseudospin-dominated lasing behavior where the topological interface states are active. Single-mode lasing is confirmed in a considerable range of gain value.
To summarize, we have constructed a lasing system with the cavity composed by the topological interface channel in dielectric photonic crystals. Our system shows typical pseudospin-dominated lasing phenomena. We are going to explore the possibility of this scheme as a promising platform for laser design.
Wu and Hu proposed a scheme to achieve topological photonic crystals by using dielectric materials. Starting from honeycomb structure, they adjust the locations of pillars and get a pair of topological edge states with opposite orbital angular momenta, which play the role of pseudospin, at the interface between topological and trivial photonic crystals. Because only dielectric materials are used, this scheme can be pushed to the optical frequency band and no external magnetic field is required.
In the present work, as the cavity for lasing, we construct the topological interface states achieved in the above scheme. We can write the equation of motion in a tight binding picture. By adjusting the real-valued hopping coefficients in the equation, we can design topological and trivial photonic crystals, between which there yield topological interface states.
By numerical solving the above equation, we successfully observe a pseudospin-dominated lasing behavior where the topological interface states are active. Single-mode lasing is confirmed in a considerable range of gain value.
To summarize, we have constructed a lasing system with the cavity composed by the topological interface channel in dielectric photonic crystals. Our system shows typical pseudospin-dominated lasing phenomena. We are going to explore the possibility of this scheme as a promising platform for laser design.