The Electron-phonon Interaction And Scattering Rate In Two Dimensional Transition Metal Dichalcogenides MoSSe

Electron-phononscatteringcanaffectthetransportpropertiesof two-dimensional transition metal dichalcogenides,which may affect the performance photoelectric devices and electrochemical devices.For example,phonon-limited carrier lifetime may hinder the ballistic transport of field effect transistor.Because many excellent properties of two-dimensional transition metal sulfides can be widely used in life,here we have investigate the electron-phonon scattering of two-dimensional transition metal dichalcogenides sulfides.Based on density functional perturbation theory,the electronic structure,phonon dispersion,carrier scattering rate and relaxation time of Janus MoSSe at 0K and 300 K and considering polarization are calculated and analyzed by using Wannier function interpolation method,and are compared with MoS₂ and MoSe₂.Through the study of the electron-phonon scattering,we have also explained in detail the contribution of optical and acoustic branches to the scattering rate of Janus MoSSe with and without polarization,and thus giving which lattice vibration mode mainly affects the hot carrier lifetime.The results show that Janus MoSSe has the same change trend of electron self-energy imaginary part and electron-phonon scattering rate under different temperatures or polarization.Both of them increase with the rising temperature,and their values are almost zero at the bottom of conduction band and the top of valence band,while the further away from band gap,the larger their values are.Under different temperatures or considering polarization,the maximum scattering rate of Janus MoSSe is between the maximum scattering rate of MoS₂ and MoSe₂.At the same time,the contribution of optical and acoustic phonons to the scattering rate of Janus MoSSe phonons is studied.The results show that the main scattering rate comes from the scattering of optical phonons at different temperatures and considering polarization,which is the same as that of MoS₂ and MoSe₂.The change trend of relaxation time and scattering rate in Janus MoSSe,MoS₂ and MoSe₂ is opposite.Under different temperature conditions,the relaxation time of Janus MoSSe at 0 K is greater than 300 K,which is consistent with the results of MoS₂ and MoSe₂.Janus MoSSe has the same change trend of relaxation time with and without polarization,but the relaxation time scales of carriers are different.Especially at the top of the valence band,the relaxation time of the Janus MoSSe decreases to 37 fs.The relaxation time of Janus MoSSe considering polarization is smaller than that of MoS₂ and MoSe₂,while at the bottom of conduction band,the relaxation time of Janus MoSSe with MoS₂ and MoSe₂ is not obvious.In the study of Janus MoSSe lattice vibration mode,the longitudinal optical vibration mode provides the main scattering mechanism for electrons and holes,and the results are the same as those of MoS₂ and MoSe₂.