Efficiently and flexibly manipulating unidirectional edge states is key to developing topological insulators as functional devices. In this work, we propose an all-optical method that utilizes the valley-selective optical Stark effect to realize programmable topological insulators. We pattern a two-dimensional honeycomb structure in an exciton-polariton platform resulting from a strong light–matter coupling in a monolayer transition metal dichalcogenide. The optical Stark effect is induced to generate a pseudo magnetic field, combined with spin–orbit coupling to form the topological one-way edge states of the polariton. On account of the ultrafast switching speed and precisely spatial controllability of the optical Stark effect, two applications, i.e., ports ratio tunable polariton splitter and programmable polariton router, were demonstrated, showing designable and rewritable functionality of all-optically controllable polariton topological insulators. This study paves the way to robustly and intelligently control/form polaritonic and spintronic devices for future classical and quantum information processing and application.

Laser emission in complex structures actively generates unclonable randomness in multidimensional domains, which has great potential for information security. Especially, developing security protocols with extended functions is urgently demanded by the Internet of Things and blockchain applications. Here, a fiber-type microcavity complex laser is developed with a random output spectrum and a bistable output intensity, wherein the dye-doped liquid crystal is used as the gain and hystereticmemory medium. The laser emits multiple spikes that vary randomly pulse-by-pulse in a relatively wide spectral band, and the logical/bistable "0" and "1" states of emission can be controlled by the photothermal effect. The lasers are proposed to act as active encryption units of end nodes in a network, wherein the spectra randomness is used to form random bit strings and the logical states are used to define the classification. Taking advantage of this hybrid advantage of complex lasing, a decentralized key distribution method is proposed with the function of key self-generation and self-direction at individual end nodes. This work would pave the way for information security in the decentralized network of multiscenario applications.

Inspired by single-molecule localization microscopy, super-resolution spectroscopy has been achieved by sparse sampling in the spectral domain, where a light source capable of randomly emitting sparse peaks plays a crucial role. Due to the intrinsic feedback mechanism of disordered light scattering, random lasers can provide the desired emission characteristics that facilitate reconstructing the detailed spectral profiles of samples. Here, we propose an all-fiber-configured coherent random laser for spectral measurement to break the instrumental response limitation of spectral detection systems. The laser remains in a chaotic regime and exhibits self-modulating spectral behavior by introducing an elaborately designed spectral tailoring element inside the cavity. The statistical number and distribution of the random peaks over the emission spectrum can be manipulated by adjusting the pump power. In addition, the laser exhibits several attractive features, such as low pumping threshold, narrow-line-width lasing modes, flexible operating wavelength range, high optical signal-to-noise ratio, and easy compatibility with optical fiber systems. Using a low-resolution spectrograph, we experimentally demonstrate super-resolution spectrum reconstruction, obtaining a spectral enhancement of around 3.3. This work provides a powerful illumination source and realization method for high-resolution spectroscopy, which is an essential tool for future optical information applications.