quantum

strong coupling

optical

semiconductor microcavities

spin hall effect

optical switch

Nature Photonics

Active optical elements with ever smaller footprint and lower energy consumption are central to modern photonics. The drive for miniaturization, speed and efficiency, with the concomitant volume reduction of the optically active area, has led to the development of devices that harness strong light–matter interactions. By managing the strength of light–matter coupling to exceed losses, quasiparticles, called exciton-polaritons, are formed that combine the properties of the optical fields with the electronic excitations of the active material. By making use of polaritons in inorganic semiconductor microcavities, all-optical transistor functionality was observed, albeit at cryogenic temperatures1. Here, we replace inorganic semiconductors with a ladder-type polymer in an optical microcavity and realize room-temperature operation of a polariton transistor through vibron-mediated stimulated polariton relaxation. We demonstrate net gain of ~10 dB μm−1, sub-picosecond switching time, cascaded amplification and all-optical logic operation at ambient conditions. Net gain of ~10 dB µm–1 and sub-picosecond switching time are shown at room temperature for optical transistors using polymers in a microcavity.

A room-temperature organic polariton transistor