河北省自然科学基金E2013407119;半导体超晶格国家重点实验室开放研究基金CHJG200701;河北科技师范学院科学研究基金1301-2506资助项目 Supported by Natural Science Foundation of Hebei ProvinceE2013407119;Open Research Foundation of State Key Laboratory of Semiconductor SuperlatticeCHJG200701;Scientific research foundation of Hebei Normal University of Science and Technology1301-2506