The research team at the University of Electronic Science and Technology of China has developed three innovative photonic devices

Recently, Professor Nie Mingming from the Key Laboratory of Fiber Optic Sensing and Communication at the School of Information and Communication Engineering, University of Electronic Science and Technology of China, in collaboration with the University of Colorado Boulder, published a research paper titled "Cross polarized stimulated Brillouin scattering empowered photonics" in the top international journal Nature Photonics. For the first time, the cross polarized Brillouin gain characteristics in lithium niobate crystals were systematically revealed, and their efficient coupling mechanism with second-order nonlinearity was demonstrated. As a result, three innovative photonic devices were successfully developed, which can provide new solutions for next-generation optical communication, precision measurement, and quantum technology.

The strong gain characteristics of the cross polarized stimulated Brillouin effect in lithium niobate, combined with its ability to control multiple physical fields such as thermo optics and electro-optic, can provide a new design dimension for new light sources and photonic integrated chips. Three innovative devices have been researched and implemented. (1) Reconfigurable stimulated Brillouin laser: By utilizing the birefringence thermal optical effect and cross polarization stimulated Brillouin effect of lithium niobate crystal, it breaks through the limitation of traditional stimulated Brillouin lasers that are difficult to tune due to fixed cavity length, and achieves sub hertz narrow linewidth laser output with arbitrary wavelength adjustment. (2) Efficient mode converter: For the first time, the Brillouin enhanced four wave mixing effect inside the cavity has been achieved, and a multi-dimensional high-efficiency mode conversion device for polarization, transverse mode, and longitudinal mode has been developed. (3) Brillouin second-order laser and frequency comb: By utilizing the synergistic effect of cross polarization Brillouin effect and second-order nonlinearity, the near-infrared and visible dual band laser and frequency comb pumped by intracavity Brillouin laser have been achieved for the first time. With the maturity of thin-film lithium niobate photonics integration technology, it is expected to use the revealed cross polarization stimulated Brillouin effect to develop more innovative photonics devices in addition to the above-mentioned devices, achieve miniaturization and low-power operation on the chip, and bring changes to cutting-edge applications such as optical atomic clocks, high-precision gyroscopes, optical communication, and optical neural networks.

This study was supported by the National Natural Science Foundation of China and the Top Basic Research Achievement Cultivation Program of the University of Electronic Science and Technology of China.

Professor Nie Mingming from the University of Electronic Science and Technology of China is the first author and co corresponding author of the paper, while Professor Shu Wei Huang from the University of Colorado Boulder is the co corresponding author of the paper.

Source: Opticsky