Stability of the positively charged manganese centre in GaAs heterostructures examined theoretically by the effective mass approximation calculation near the $\varGamma$ critical point
Wang Li-Guo(王丽国), Shen Chao(申超), Zheng Hou-Zhi(郑厚植), Zhu Hui(朱汇), and Zhao Jian-Hua(赵建华)