2M − WSe2最近實驗上在常壓下展現出弱拓樸絕緣體相，同時在實驗中在10.7十億帕時呈現最大的超導臨界溫度7.3克耳文。為了展示在高壓下弱拓樸絕緣體相和超導的共存，我們首先通過能帶結構的軌域貢獻和奇偶分析來表徵2M − WSe2在不同壓力下的拓樸性質，揭示2M − WSe2在0至150千巴範圍內仍然是一個弱拓樸絕緣體。為了研究超導的出現，我們使用了在EPW套件中實現的電子聲子瓦尼爾傅立葉插值。我們發現增強的電子聲子耦合強度λ歸因於在Γ − Y方向上出現的一個能帶袋。

2M − WSe2 is recently shown to hold the weak topological insulator (WTI) phase at ambient pressure and present the superconductivity with a maximum $T_c=$ 7.3 K at 10.7 GPa, experimentally. To show the coexistence of WTI phase and the emergence of superconductivity at high pressure, we initially characterize the topological properties in 2M − WSe2 as a function of pressure with the orbital-resolved band structure and parity analysis, revealing that 2M − WSe2 is still a WTI at several pressures ranging from 0 to 150 Kbar. To investigate the emergence of superconductivity, we employ the electron-phonon Wannier Fourier interpolation as implemented in EPW package. We find out that the enhanced electron-phonon coupling strength λ is attributed to the emergence of a pocket along the Γ − Y direction.

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