On-chip Mach-Zehnder interferometer for 1550 nm laser frequency stabilization.

Low-noise stable lasers have broad applications in metrology, spectroscopy, communication, and quantum physics. Here we demonstrate locking a semiconductor laser to an on-chip silicon nitride Mach-Zehnder interferometer (MZI) using the Pound-Drever-Hall (PDH) stabilization technology. After locking, the frequency noise of the laser is suppressed by up to 37 dB, and the relative stability reaches 3 10 at a gate time of 1 ms, showing an order of magnitude improvement compared to a free-running operation.

High-Capacity Multilayered Luminescent Encryption Technology Based on Er-Implanted Silicon Treated by Pulsed Laser Annealing.

Luminescent encrypted labels can effectively solve the problem of counterfeiting. However, they suffer from complex design and fabrication, low space utilization, and limited capacity of encrypted information. Herein, we create multilayer infrared luminescent encryption labels using femtosecond-laser-activated Er-doped silicon.