Visible-to-ultraviolet-C upconverted photon for multifunction via Ca2SiO4:Pr3.

The ultraviolet C (UVC) photon plays a key role in a broad spectrum of fields. With the implementation of the Minamata Convention, searching for a new way to achieve UVC light is highly desired. Here we develop a material of Ca2SiO4:Pr3+ that can emit UVC light upon excitation of a 450-nm laser or even a very cheap 450-nm LED, a fact confirmed by using a solar blind camera to capture UVC emission from Ca2SiO4:Pr3+. In addition, smart anti-counterfeiting and inactivation of Bacillus subtilis applications using Ca2SiO4:Pr3+ are also confirmed.

Nanosecond tunable laser for the all-optical switching network.

The optically switched network can offset the increasing gap between datacenter traffic growth and electrical switch capacity due to the slowdown of Moore's law. Ultra-high-speed wavelength tunable lasers are especially vital for the high integration and performance improvement of the all-optical switching system. In this paper, a fast tunable laser based on a laser array is realized. The 2×8 matrix structure of the laser array is fabricated by the reconstruction-equivalent-chirp (REC) technique. Aiming at the 2×8 array, a drive control system is designed to provide stable and fast switching, to achieve high-speed switching of the laser wavelength, and to keep the wavelength stable after switching. The simulation and experimental results show that the switching time between any two wavelength channels of the laser is less than 10 ns. The switching time of any two channels of the laser can be reduced by 2-3 ns after the pre-emphasis processing of the electrical signal.