title: Tuning carrier lifetime in InGaN/GaN LEDs via strain compensation for high-speed visible light communication.
abstract: In recent years, visible light communication (VLC) technology has attracted intensive attention due to its huge potential in superior processing ability and fast data transmission. The transmission rate relies on the modulation bandwidth, which is predominantly determined by the minority-carrier lifetime in III-group nitride semiconductors. In this paper, the carrier dynamic process under a stress field was studied for the first time, and the carrier recombination lifetime was calculated within the framework of quantum perturbation theory. Owing to the intrinsic strain due to the lattice mismatch between InGaN and GaN, the wave functions for the holes and electrons are misaligned in an InGaN/GaN device. By applying an external strain that "cancels" the internal strain, the overlap between the wave functions can be maximized so that the lifetime of the carrier is greatly reduced. As a result, the maximum speed of a single chip was increased from 54 MHz up to 117 MHz in a blue LED chip under 0.14% compressive strain. Finally, a bandwidth contour plot depending on the stress and operating wavelength was calculated to guide VLC chip design and stress optimization.
authors.affiliation: Beijing Institute of Nanoenergy and Nanosystems, Chinese Academy of Sciences, National Center for Nanoscience and Technology (NCNST), Beijing, 100083, P. R. China.
authors.forename: Chunhua
authors.initials: C
authors.lastname: Du
authors.affiliation: Beijing Institute of Nanoenergy and Nanosystems, Chinese Academy of Sciences, National Center for Nanoscience and Technology (NCNST), Beijing, 100083, P. R. China.
authors.forename: Xin
authors.initials: X
authors.lastname: Huang
authors.affiliation: Beijing Institute of Nanoenergy and Nanosystems, Chinese Academy of Sciences, National Center for Nanoscience and Technology (NCNST), Beijing, 100083, P. R. China.
authors.forename: Chunyan
authors.initials: C
authors.lastname: Jiang
authors.affiliation: Beijing Institute of Nanoenergy and Nanosystems, Chinese Academy of Sciences, National Center for Nanoscience and Technology (NCNST), Beijing, 100083, P. R. China.
authors.forename: Xiong
authors.initials: X
authors.lastname: Pu
authors.affiliation: Beijing Institute of Nanoenergy and Nanosystems, Chinese Academy of Sciences, National Center for Nanoscience and Technology (NCNST), Beijing, 100083, P. R. China.
authors.forename: Zhenfu
authors.initials: Z
authors.lastname: Zhao
authors.affiliation: Beijing Institute of Nanoenergy and Nanosystems, Chinese Academy of Sciences, National Center for Nanoscience and Technology (NCNST), Beijing, 100083, P. R. China.
authors.forename: Liang
authors.initials: L
authors.lastname: Jing
authors.affiliation: Beijing Institute of Nanoenergy and Nanosystems, Chinese Academy of Sciences, National Center for Nanoscience and Technology (NCNST), Beijing, 100083, P. R. China.
authors.forename: Weiguo
authors.initials: W
authors.lastname: Hu
authors.affiliation: Beijing Institute of Nanoenergy and Nanosystems, Chinese Academy of Sciences, National Center for Nanoscience and Technology (NCNST), Beijing, 100083, P. R. China.|School of Materials Science and Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332-0245, United States.
authors.forename: Zhong Lin
authors.initials: ZL
authors.lastname: Wang