Modulation of carrier lifetime in MoS<sub>2</sub> monolayer by uniaxial strain

Modulation of carrier lifetime in MoS₂ monolayer by uniaxial strain

Hong Hao¹, Cheng Yang¹, Wu Chunchun^{1, 2}, Huang Chen¹, Liu Can¹, Yu Wentao¹, Zhou Xu¹, Ma Chaojie¹, Wang Jinhuan^{1, 3}, Zhang Zhihong¹, Zhao Yun³, Xiong Jie², Liu Kaihui^{1, †}

Characterization of the carrier lifetime in MoS₂: (a) Illustration of four different channels for carrier recombination at the band edge of MoS₂ (i.e., Auger scattering (τ₁), trap by defect states (τ₂), carrier–phonon scattering (τ₃), and electron–hole radiative recombination (τ₄)). (b) Schematics of the optical pump–probe and time-resolved PL setup. (c) The 2D plots of MoS₂ transient absorption at different probe wavelengths with pump wavelength of 410 nm. (d) Evolution of transient absorption signal with probe wavelength at 670 nm. The transient absorption signal undergoes biexponential decay with lifetimes of 0.38 ps and 2.3 ps, corresponding to lifetimes of Auger scattering and trapping by defect states respectively. (e) Time-resolved PL spectrum of MoS₂. The spectrum demonstrates the dynamic channels of carrier–phonon scattering and electron–hole radiative recombination, with lifetimes of 25 ps and 150 ps, respectively.