Optoelectronic properties of bottom gate-defined in-plane monolayer WSe<sub>2</sub> p–n junction<xref rid="cpb_27_8_087303fn1" ref-type="fn">*</xref><fn id="cpb_27_8_087303fn1"><label>*</label><p>Project supported by the National Key Research and Development Program of China (Grant No. 2016YFA0301700), the National Natural Science Foundation of China (Grant Nos. 61590932, 11774333, 61674132, 11674300, 11575172, and 11625419), the Anhui Provincial Initiative in Quantum Information Technologies, China (Grant Nos. AHY080000 and AHY130300), the Strategic Priority Research Program of the Chinese Academy of Sciences (Grant No. XDB24030601), and the Fundamental Research Funds for the Central Universities, China. This work was partially carried out at the USTC Center for Micro and Nanoscale Research and Fabrication.</p></fn>

Optoelectronic properties of bottom gate-defined in-plane monolayer WSe₂ p–n junction**

Project supported by the National Key Research and Development Program of China (Grant No. 2016YFA0301700), the National Natural Science Foundation of China (Grant Nos. 61590932, 11774333, 61674132, 11674300, 11575172, and 11625419), the Anhui Provincial Initiative in Quantum Information Technologies, China (Grant Nos. AHY080000 and AHY130300), the Strategic Priority Research Program of the Chinese Academy of Sciences (Grant No. XDB24030601), and the Fundamental Research Funds for the Central Universities, China. This work was partially carried out at the USTC Center for Micro and Nanoscale Research and Fabrication.

Liu Di^{1, 2}, Qi Xiao-Zhuo^{1, 2}, Taniguchi Takashi³, Ren Xi-Feng^{1, 2, †}, Guo Guo-Ping^{1, 2, ‡}

(color online) (a) Experimental setup used to measure photocurrent and PL in our WSe₂ PN junction. (b) The I–V curve of the device in the PN regime (V_lg = −4 V, V_rg = 6 V) in the dark and the I–V curve under a laser exposure (2 μW) in the middle of the WSe₂. (c) Schematic band diagrams of the WSe₂ PN junction under laser exciting.