In a new development, scientists at KAIST have developed a laser system that produces quantum particles with two-way communication at room temperature. The findings published in Nature Photonics could lead to one microcavity laser system that needs low level of threshold energy as its energy loss increases.
Meanwhile, the system involves shining light via a single hexagonally shaped microcavity treated with a silicon nitride substrate modulated for loss. The design of the system is exciting. This is because at room temperature it leads to production of a polariton laser, which usually requires subzero temperatures.
Besides this, the researchers found another counter-intuitive and unique feature of the design. Usually, the energy is lost at the time of laser operation. But, as energy loss increases in the new system, the amount of energy needed for lasing decreased. Therefore, exploiting this phenomenon could lead to development of high efficiency lasers, of low threshold, for future quantum optical devices.
Elaborating on the system, it applies a concept of quantum physics termed parity-time reversal symmetry. The platform is important that allows energy loss to find use as gain. Reducing laser threshold energy for customary optical devices and sensors, quantum devices, and controlling the direction of light are some places where the system is used.
Importantly, design and materials is the key of the system. The hexagonal microcavity separates light particles in two different modes: one that crosses the upward-facing triangle of hexagon and another that passes through the downward-facing triangle. The light particles of both modes have the same path and energy but don’t interact with each other.
Nonetheless, the light particles interact with excitons discharged by hexagonal microcavity.