title: Distinct enhancement of sub-bandgap photoresponse through intermediate band in high dose implanted ZnTe:O alloys.
abstract: The demand for high efficiency intermediate band (IB) solar cells is driving efforts in producing high quality IB photovoltaic materials. Here, we demonstrate ZnTe:O highly mismatched alloys synthesized by high dose ion implantation and pulsed laser melting exhibiting optically active IB states and efficient sub-gap photoresponse, as well as investigate the effect of pulsed laser melting on the structural and optical recovery in detail. The structural evolution and vibrational dynamics indicates a significant structural recovery of ZnTe:O alloys by liquid phase epitaxy during pulsed laser melting process, but laser irradiation also aggravates the segregation of Te in ZnTe:O alloys. A distinct intermediate band located at 1.8 eV above valence band is optically activated as evidenced by photoluminescence, absorption and photoresponse characteristics. The carrier dynamics indicates that carriers in the IB electronic states have a relatively long lifetime, which is beneficial for the fast separation of carriers excited by photons with sub-gap energy and thus the improved overall conversion efficiency. The reproducible capability of implantation and laser annealing at selective area enable the realization of high efficient lateral junction solar cells, which can ensure extreme light trapping and efficient charge separation.
authors.affiliation: Jiangsu Provincial Key Laboratory of Advanced Photonic and Electronic Materials, and School of Electronic Science and Engineering, Nanjing University, Nanjing 210093, China.
authors.forename: Jing
authors.initials: J
authors.lastname: Li
authors.affiliation: Jiangsu Provincial Key Laboratory of Advanced Photonic and Electronic Materials, and School of Electronic Science and Engineering, Nanjing University, Nanjing 210093, China.|Department of Electronic Materials Engineering, Research School of Physics and Engineering, The Australian National University, Canberra 2601, Australia.
authors.forename: Jiandong
authors.initials: J
authors.lastname: Ye
authors.affiliation: Jiangsu Provincial Key Laboratory of Advanced Photonic and Electronic Materials, and School of Electronic Science and Engineering, Nanjing University, Nanjing 210093, China.|Department of Electronic Materials Engineering, Research School of Physics and Engineering, The Australian National University, Canberra 2601, Australia.
authors.forename: Fangfang
authors.initials: F
authors.lastname: Ren
authors.affiliation: Jiangsu Provincial Key Laboratory of Advanced Photonic and Electronic Materials, and School of Electronic Science and Engineering, Nanjing University, Nanjing 210093, China.
authors.forename: Dongming
authors.initials: D
authors.lastname: Tang
authors.affiliation: Jiangsu Provincial Key Laboratory of Advanced Photonic and Electronic Materials, and School of Electronic Science and Engineering, Nanjing University, Nanjing 210093, China.
authors.forename: Yi
authors.initials: Y
authors.lastname: Yang
authors.affiliation: Jiangsu Provincial Key Laboratory of Advanced Photonic and Electronic Materials, and School of Electronic Science and Engineering, Nanjing University, Nanjing 210093, China.
authors.forename: Kun
authors.initials: K
authors.lastname: Tang
authors.affiliation: Jiangsu Provincial Key Laboratory of Advanced Photonic and Electronic Materials, and School of Electronic Science and Engineering, Nanjing University, Nanjing 210093, China.
authors.forename: Shulin
authors.initials: S
authors.lastname: Gu
authors.affiliation: Jiangsu Provincial Key Laboratory of Advanced Photonic and Electronic Materials, and School of Electronic Science and Engineering, Nanjing University, Nanjing 210093, China.
authors.forename: Rong
authors.initials: R
authors.lastname: Zhang
authors.affiliation: Jiangsu Provincial Key Laboratory of Advanced Photonic and Electronic Materials, and School of Electronic Science and Engineering, Nanjing University, Nanjing 210093, China.
authors.forename: Youdou
authors.initials: Y
authors.lastname: Zheng