A method for preparing saturable absorber devices based on black phosphorus

Abstract

The invention discloses a method for preparing a saturable absorber device based on black phosphorus. In this method, the two-dimensional layered black phosphorus obtained by mechanical exfoliation, or the two-dimensional layer distributed in the alcohol solution obtained by ultrasonic vibration Shaped black phosphorus is deposited on the optical fiber head by directional transfer method as the saturable absorbing layer of the device. The directional transfer method involved in the present invention can effectively and efficiently transfer black phosphorus to the optical fiber head, avoiding damage to the material during the manual transfer process, and can accurately locate the position of the nano-scale material, avoiding blindness The transfer problem improves the success rate of saturable absorber preparation. The black phosphorus saturable absorber made by the method of the invention works in a transmission mode, can realize the ultrashort pulse output of the laser in the near-middle infrared working band, has the characteristics of good performance and strong compatibility, and is suitable for Q-switching and locking of the laser applications such as analog and optical signal processing.

Description

Technical field [0001] The invention belongs to the field of saturable absorbers of pulsed lasers, and in particular relates to a method for preparing saturable absorber devices used for Q-switching, mode locking, optical signal processing and the like in lasers. Background technique [0002] At present, the saturable absorber device mainly used in the market is the semiconductor saturable absorber mirror (SESAM), but the semiconductor saturable absorber mirror has many disadvantages that are difficult to overcome. First of all, SESAM requires a complex and expensive clean room-based manufacturing system with complex manufacturing processes and high costs. Secondly, due to the inherent band gap of group III-IV semiconductors, the saturated absorption spectrum is narrow, and is basically limited to the near-infrared band. In the far-infrared band, there is currently no SESAM available; thirdly, the optical damage threshold of SESAM is also very low, making it difficult to apply in...

AI Technical Summary

Problems solved by technology

However, so far, black phosphorus has not been successfully made into a saturable absorber and applied to fiber lasers

The main difficulties are: 1. Black phosphorus is unstable and easily denatured when exposed to the air; 2. The growth conditions of black phosphorus are far harsher than graphene, and it is currently impossible to grow large-area films by chemical vapor deposition like graphene , nanoscale black phosphorus flakes can only be obtained by mechanical stripping or liquid phase separation, and it is difficult to align and transfer them to the fiber core with a diameter of less than 10 μm

Images