title: Electrically Tunable Valley-Light Emitting Diode (vLED) Based on CVD-Grown Monolayer WS2.
abstract: Owing to direct band gap and strong spin-orbit coupling, monolayer transition-metal dichalcogenides (TMDs) exhibit rich new physics and great applicable potentials. The remarkable valley contrast and light emission promise such two-dimensional (2D) semiconductors a bright future of valleytronics and light-emitting diodes (LEDs). Though the electroluminescence (EL) has been observed in mechanically exfoliated small flakes of TMDs, considering real applications, a strategy that could offer mass-product and high compatibility is greatly demanded. Large-area and high-quality samples prepared by chemical vapor deposition (CVD) are perfect candidates toward such goal. Here, we report the first demonstration of electrically tunable chiral EL from CVD-grown monolayer WS2 by constructing a p-i-n heterojunction. The chirality contrast of the overall EL reaches as high as 81% and can be effectively modulated by forward current. The success of fabricating valley LEDs based on CVD WS2 opens up many opportunities for developing large-scale production of unconventional 2D optoelectronic devices.
authors: Nanjing Tech Center of Research and Development, Nanjing Tech University , Nanjing 211816, People's Republic of China.|Division of Physics and Applied Physics, School of Physical and Mathematical Sciences, Nanyang Technological University , Singapore 637371.
authors: Weihuang
authors: W
authors: Yang
authors: Division of Physics and Applied Physics, School of Physical and Mathematical Sciences, Nanyang Technological University , Singapore 637371.
authors: Jingzhi
authors: J
authors: Shang
authors: Key Laboratory of Flexible Electronics (KLOFE) and Institue of Advanced Materials (IAM), National Jiangsu Synergistic Innovation Center for Advanced Materials (SICAM), Nanjing Tech University (Nanjing Tech) , 30 South Puzhu Road, Nanjing 211816, People's Republic of China.
authors: Jianpu
authors: J
authors: Wang
authors: Division of Physics and Applied Physics, School of Physical and Mathematical Sciences, Nanyang Technological University , Singapore 637371.
authors: Xiaonan
authors: X
authors: Shen
authors: Division of Physics and Applied Physics, School of Physical and Mathematical Sciences, Nanyang Technological University , Singapore 637371.
authors: Bingchen
authors: B
authors: Cao
authors: Division of Physics and Applied Physics, School of Physical and Mathematical Sciences, Nanyang Technological University , Singapore 637371.
authors: Namphung
authors: N
authors: Peimyoo
authors: Division of Physics and Applied Physics, School of Physical and Mathematical Sciences, Nanyang Technological University , Singapore 637371.
authors: Chenji
authors: C
authors: Zou
authors: Division of Physics and Applied Physics, School of Physical and Mathematical Sciences, Nanyang Technological University , Singapore 637371.
authors: Yu
authors: Y
authors: Chen
authors: Division of Physics and Applied Physics, School of Physical and Mathematical Sciences, Nanyang Technological University , Singapore 637371.
authors: Yanlong
authors: Y
authors: Wang
authors: Division of Physics and Applied Physics, School of Physical and Mathematical Sciences, Nanyang Technological University , Singapore 637371.
authors: Chunxiao
authors: C
authors: Cong
authors: Nanjing Tech Center of Research and Development, Nanjing Tech University , Nanjing 211816, People's Republic of China.|Key Laboratory of Flexible Electronics (KLOFE) and Institue of Advanced Materials (IAM), National Jiangsu Synergistic Innovation Center for Advanced Materials (SICAM), Nanjing Tech University (Nanjing Tech) , 30 South Puzhu Road, Nanjing 211816, People's Republic of China.|Key Laboratory for Organic Electronics and Information Displays (KLOEID) and Institute of Advanced Materials (IAM), Nanjing University of Posts and Telecommunications , Nanjing 210023, Jiangsu, People's Republic of China.
authors: Wei
authors: W
authors: Huang
authors: Division of Physics and Applied Physics, School of Physical and Mathematical Sciences, Nanyang Technological University , Singapore 637371.|Department of Physics, Faculty of Science, National University of Singapore , Singapore 117542.
authors: Ting
authors: T
authors: Yu
keywords: 2D semiconductor; WS2; chemical vapor deposition; chiral electroluminescence; light-emitting diode; valley polarization