[1] Mak K F, Lee C, Hone J, et al. Atomically thin MoS2: a new direct-gap semiconductor［J］. Physical Review Letters, 2010, 105(13): 136805.

[2] Li J L, Tang B, Yuan B, et al. A review of optical imaging and therapy using nanosized graphene and graphene oxide［J］. Biomaterials, 2013, 34(37): 9519-9534.

[3] Mak K F, Ju L, Wang F, et al. Optical spectroscopy of graphene: from the far infrared to the ultraviolet［J］. Solid State Communications, 2012, 152(15): 1341-1349.

[4] Splendiani A, Sun L, Zhang Y, et al. Emerging photoluminescence in monolayer MoS2［J］. Nano Letters, 2010, 10(4): 1271-1275.

[5] Britnell L, Ribeiro R M, Eckmann A, et al. Strong light-matter interactions in heterostructures of atomically thin films［J］. Science, 2013, 340(6138): 1311-1314.

[6] Qiu D Y, Da Jornada F H, Louie S G. Optical spectrum of MoS2: many-body effects and diversity of exciton states［J］. Physical Review Letters, 2013, 111(21): 216805.

[7] Schuller J A, Karaveli S, Schiros T, et al. Orientation of luminescent excitons in layered nanomaterials［J］. Nature Nanotechnology, 2013, 8(4): 271-276.

[8] Mak K F, He K, Lee C, et al. Tightly bound trions in monolayer MoS2［J］. Nature Materials, 2013, 12(3): 207-211.

[9] Tongay S, Zhou J, Ataca C, et al. Broad-range modulation of light emission in two-dimensional semiconductors by molecular physisorption gating［J］. Nano Letters, 2013, 13(6): 2831-2836.

[10] Nan H, Wang Z, Wang W, et al. Strong photoluminescence enhancement of MoS2 through defect engineering and oxygen bonding［J］. ACS Nano, 2014, 8(6): 5738-5745.

[11] Amani M, Lien D H, Kiriya D, et al. Near-unity photoluminescence quantum yield in MoS2［J］. Science, 2015, 350(6264): 1065-1068.

[12] Ross J S, Klement P, Jones A M, et al. Electrically themally excitonic light-emitting diodes based on monolayer WSe2 p-n junctions［J］. Nature Nanotechnology, 2014, 9(4): 268-272.

[13] Withers F, Del Pozo-Zamudio O, Mishchenko A, et al. Light-emitting diodes by band-structure engineering in van der Waals heterostructures［J］. Nature Materials, 2015, 14(3): 301-306.

[14] Wu S, Buckley S, Schaibley J R, et al. Monolayer semiconductor nanocavity lasers with ultralow thresholds［J］. Nature, 2015, 520(7545): 69-72.

[15] Salehzadeh O, Djavid M, Tran N H, et al. Optically pumped two-dimensional MoS2 lasers operating at room-temperature［J］. Nano Letters, 2015, 15(8): 5302-5306.

[16] Li H, Wu J, Yin Z, et al. Preparation and applications of mechanically exfoliated single-layer and multilayer MoS2 and WSe2 nanosheets［J］. Accounts of Chemical Research, 2014, 47(4): 1067-1075.

[17] Lin Y C, Dumcenco D O, Huang Y S, et al. Atomic mechanism of the semiconducting-to-metallic phase transition in single-layered MoS2［J］. Nature Nanotechnology, 2014, 9(5): 391-396.

[18] Lv R, Robinson J A, Schaak R E, et al. Transition metal dichalcogenides and beyond: synthesis, properties, and applications of single- and few-layer nanosheets［J］. Accounts of Chemical Research, 2014, 48(1): 56-64.

[19] zgür , Alivov Y I, Liu C, et al. A comprehensive review of ZnO materials and devices［J］. Journal of Applied Physics, 2005, 98(4): 041301.

[20] He K, Kumar N, Zhao L, et al. Tightly bound excitons in monolayer WSe2［J］. Physical Review Letters, 2014, 113(2): 026803.

[21] Ross J S, Wu S F, Yu H Y, et al. Electrical control of neutral and charged excitons in a monolayer semiconductor［J］. Nature Communications, 2013, 4: 1474.

[22] You Y M, Zhang X X, Berkelbach T C, et al. Observation of biexcitons in monolayer WSe2［J］. Nature Physics, 2015, 11(6): 477-481.

[23] Tongay S, Suh J, Ataca C, et al. Defects activated photoluminescence in two-dimensional semiconductors: interplay between bound, charged, and free excitons［J］. Scientific Reports, 2013, 3: 2657.

[24] Cheiwchanchamnangij T, Lambrecht W R L. Quasiparticle band structure calculation of monolayer, bilayer, and bulk MoS2［J］. Physical Review B, 2012, 85(20): 205302.

[25] Zeng H, Cui X. An optical spectroscopic study on two-dimensional group-VI transition metal dichalcogenides［J］. Chemical Society Reviews, 2015, 44(9): 2629-2642.

[26] Zhao W J, Ghorannevis Z, Chu L Q, et al. Evolution of electronic structure in atomically thin sheets of WS2 and WSe2［J］. ACS Nano, 2012, 7(1): 791-797.

[27] Jariwala B, Voiry D, Jindal A, et al. Synthesis and characterization of ReS2 and ReSe2 layered chalcogenide single crystals［J］. Chemistry of Materials, 2016, 28(10): 3352-3359.

[28] Huang C C, Kao C C, Lin D Y, et al. A comprehensive study on the optical properties of thin gold-doped Rhenium disulphide layered single crystals［J］. Japanese Journal of Applied Physics, 2013, 52(4S): 04CH11.

[29] Zhou W, Zou X, Najmaei S, et al. Intrinsic structural defects in monolayer molybdenum disulfide［J］. Nano Letters, 2013, 13(6): 2615-2622.

[30] Yu Z G, Zhang Y W, Yakobson B I. An anomalous formation pathway for dislocation-sulfur vacancy complexes in polycrystalline monolayer MoS2［J］. Nano Letters, 2015, 15(10): 6855-6861.

[31] Hong J H, Hu Z X, Probert M, et al. Exploring atomic defects in molybdenum disulphide monolayers［J］. Nature Communications, 2015, 6: 6293.

[32] Zafar A, Nan H Y, Zafar Z, et al. Probing the intrinsic optical quality of CVD grown MoS2［J］. Nano Research, 2016, 9(6): 1752-1762.

[33] Shi H, Yan R, Bertolazzi S, et al. Exciton dynamics in suspended monolayer and few-layer MoS2 2D crystals［J］. ACS Nano, 2013, 7(2): 1072-1080.

[34] Komsa H P, Kotakoski J, Kurasch S, et al. Two-dimensional transition metal dichalcogenides under electron irradiation: defect production and doping［J］. Physical Review Letters, 2012, 109(3): 035503.

[35] van der Zande A M, Huang P Y, Chenet D A, et al. Grains and grain boundaries in highly crystalline monolayer molybdenum disulphide［J］. Nature Materials, 2013, 12(6): 554-561.

[36] Gan X, Gao Y, Mak K F, et al. Controlling the spontaneous emission rate of monolayer MoS2 in a photonic crystal nanocavity［J］. Applied Physics Letters, 2013, 103(18): 181119.

[37] Strauf S, Hennessy K, Rakher M T, et al. Self-tuned quantum dot gain in photonic crystal lasers［J］. Physical Review Letters, 2006, 96(12): 127404.

[38] Strauf S, Jahnke F. Single quantum dot nanolaser［J］. Laser & Photonics Reviews, 2011, 5(5): 607-633.

[39] Ellis B, Mayer M A, Shambat G, et al. Ultralow-threshold electrically pumped quantum-dot photonic-crystal nanocavity laser［J］. Nature Photonics, 2011, 5(5): 297-300.

[40] Wu S F, Buckley S, Jones A M, et al. Control of two-dimensional excitonic light emission via photonic crystal［J］. 2D Materials, 2014, 1(1): 011001.

[41] Tanaka Y, Asano T, Akahane Y, et al. Theoretical investigation of a two-dimensional photonic crystal slab with truncated cone air holes［J］. Applied Physics Letters, 2003, 82(11): 1661-1663.

[42] Ye Y, Wong Z J, Lu X, et al. Monolayer excitonic laser［J］. Nature Photonics, 2015(9): 733-737.

[43] Wang Q H, Kalantar-Zadeh K, Kis A, et al. Electronics and optoelectronics of two-dimensional transition metal dichalcogenides［J］. Nature Nanotechnology, 2012, 7(11): 699-712.

[44] Liu X, Galfsky T, Sun Z, et al. Strong light-matter coupling in two-dimensional atomic crystals［J］. Nature Photonics, 2015, 9(1): 30-34.

[45] Meng X, Grote R R, Jin W C, et al. Rigorous theoretical analysis of a surface-plasmon nanolaser with monolayer MoS2 gain medium［J］. Optics Letters, 2016, 41(11): 2636-2639.

[46] Yokoyama H, Brorson S D. Rate equation analysis of microcavity lasers［J］. Journal of Applied Physics, 1989, 66(10): 4801-4805.