Cui Bi-Feng, Li Jian-Jun, Zou De-Shu, Lian Peng, Han Jin-Ru, Wang Dong-Feng, Du Jin-Yu, Liu Ying, Zhao Hui-Min, Shen Guang-Di. Large optical cavity and small vertical divergence angle semiconductor lasersJ. Acta Physica Sinica, 2004, 53(7): 2150-2153. DOI: 10.7498/aps.53.2150