Project 26: All-fiber Acousto-optic Modulator
Contact Information:
Assoc. Prof. Qingwen Liu
Email: liuqingwen@sjtu.edu.cn
Project Description and Objectives:
An Acousto-optic Modulator (AOM) uses acousto-optic effect to realize the modulation of frequency, amplitude and phase of light. It has a wide range of applications in lasers, optical radar and other fields. AOM based on crystalline and free-space coupling inevitably suffer from the shortcomings of large insertion loss and high cost, while the AOM with all-fiber structure solves the above problems well. However, it is difficult for the acoustic wave to induce a large refractive index modulation in the optical fiber, results in low efficiency of the all-fiber AOM. In this project, new structures of the fiber will be designed, with which the refractive index modulation depth of fiber can be significantly enhanced, so as to realize an all-fiber acousto-optic modulator with high efficiency and compact structure.
Eligibility Requirements:
Basic understanding of photonics and fiber optics.
Main Tasks:
Study the basics of few-mode fibers and figure out the intensity and phase distribution of each mode.
Learn the principle of holography technology, and recover the wave front of one single mode using the holography figure captured by the digital camera.
Set-up the system and realize the coherent detection through the digital camera with a reference beam.
Learn how to recover all the modes from the few-mode fibers, and compare the shape of the recovered mode with the theoretical modes in few-mode fibers.
Website:
School: http://www.cs.sjtu.edu.cn/PeopleDetail.aspx?id=87