Defect-induced Raman phonons in the van der Waals bonded ferromagnet Fe₃GeTe₂

【作者】 程国峰； 黄枭坤； 尹晗迪； 姜斌斌； 王伟； 孙玥； 阮音捷；

【机构】 中国科学院上海硅酸盐研究所； 景德镇陶瓷大学材料科学与工程学院； 南京工业大学柔性电子重点实验室；

【摘要】 Based on First-principles calculations and Raman Scattering studies,we report the assigned Raman modes in Fe-deficient van der Waals bonded ferromagnet Fe_2.8GeTe₂.Results show that Fe vacancies in Fe_2.8GeTe₂ may induce some vibrational modes,which merge together as a broad Raman peak at 155 cm^-1.Seven Raman-active modes assigned as E_2g and A_1g are predicted,and observed individually.In addition,the temperature dependence of Raman frequencies tells the magnetic-order-induced phonon behaviors by strong spin-lattice coupling,which indicates the impact of Fe-deficiency on the magnetic transition.The Raman phonons we present are predicted to detect the Fe-deficiency,especially in Fe₃GeTe₂ nanoscale devices.更多还原

【Abstract】 Based on First-principles calculations and Raman Scattering studies,we report the assigned Raman modes in Fe-deficient van der Waals bonded ferromagnet Fe_2.8GeTe₂.Results show that Fe vacancies in Fe_2.8GeTe₂ may induce some vibrational modes,which merge together as a broad Raman peak at 155 cm^-1.Seven Raman-active modes assigned as E_2g and A_1g are predicted,and observed individually.In addition,the temperature dependence of Raman frequencies tells the magnetic-order-induced phonon behaviors by strong spin-lattice coupling,which indicates the impact of Fe-deficiency on the magnetic transition.The Raman phonons we present are predicted to detect the Fe-deficiency,especially in Fe₃GeTe₂ nanoscale devices.更多还原