Tian Jing, Hou Mei-Jiang, Jiang Yang, Zhang Hong-Xu, Bai Guang-Fu, Feng Hao. High sensitivity fiber displacement sensor based compound ring laser cavity with linear variation of beat frequency signalJ. Acta Physica Sinica, 2020, 69(18): 184217. DOI: 10.7498/aps.69.20200385