Since Miyasaka and co-workers open the door of the hybrid organic-inorganic halide perovskite AMX3 (where A is an organic cation, M = Pb, Sn, or Ge, and X = I, Br, or Cl), it has attracted increasing attention from the photovoltaic community. More information about this kind of new material has been revealed through the calculation of the complicated densities functional theory (DFT). Here, we report a new simple 8-band k.p method to calculate the band structure and optical properties of cubic CsSnBr3 perovskite. The bulk inversion asymmetry δz=δxy=500 meV is taken into consideration in our model. The band splitting caused by the bulk inversion asymmetry is observed at non-R point.

W. J. Fan received the B. Eng degree in applied physics from National University of Defense Technology, Changsha, China, in 1987, the M. S. degree from the Institute of Semiconductors, Chinese Academy of Science, Beijing, China, in 1990, and the Ph. D. degree in electrical engineering from National University of Singapore, in 1997. From 1990 to 1994, he joined the Institute of Semiconductors, Chinese Academy of Science as a Research Assistant. From 1996 to 1999, he joined MBE Technology Pte. Ltd., Singapore as a System Engineer. From 1999 to 2000, he was a Process Engineer at Agilent Technologies, Singapore. From 2000 to 2005, he was an Assistant Professor in Nanyang Technological University. From 2005 to now, he is an Associate Professor in Nanyang Technological University. His research interests include semiconductor band structure calculations; semiconductor material growth, characterizations and photonic device fabrications; Si photonics; Spintronics. He authored/co-authored > 120 refereed journal papers and >90 conference presentations including 9 plenary/invited talks. According to SCI (Web of Science), the total external citations > 1900 times, his h index is 21. He co-authored two book chapters. He awarded JAP outstanding author in 2013. The granted research funding > S$3.9 M from MOE, ASTAR, DARPA(USA) and NSG(Japan) as PI/Co-PI. He graduated > 8 PhD students as Main/Co-supervisor. He visited MIT, Lehigh, Southampton, Bristol, and Aston Universities. He was the scientific committee member, reviewer and optoelectronics session co-chair of Symposium J of ICMAT 2005. He was the Technical Programme Committee Member of Integrated Optoelectronic Devices and Optical Processors of the 43rd European Conference on Optical Communication (ECOC) 2017, Sweden. He served as Chair of Symposium B of the 9th International Conference on Materials for Advanced Technologies, Singapore 2017, and Co-Chair of CLEO-PR, OECC and PGC 2017: Symposium J1 Semiconductor and Integrated Optical Devices. He served as reviewer of APPL PHYS LETT, J APPL PHYS, NANO LETTERS etc.