拓扑半金属二碲化铂太赫兹探测器

The energy band structure and topological surface states of the type-II Dirac semimetal platinum ditelluride (PtTe₂) were calculated by first-principles. Layered PtTe₂ was prepared by the mechanical exfoliation method, and a metal - PtTe₂ - metal field-effect transistor was fabricated through micro-nano processing. The photocurrent response of the field-effect transistor device based on the type-II Dirac semimetal PtTe₂ in the terahertz band was studied. The device has an obvious optical response to terahertz, with a responsivity reaching 3.85 A/W and an equivalent noise power of about 4.81 pW·Hz⁻¹/². It has broad application prospects in the low-energy region, especially in the terahertz band.

通过第一性原理计算了第Ⅱ类狄拉克半金属二碲化铂(PtTe_2)的能带结构及拓扑表面态,使用机械剥离法制备出层状PtTe_2,通过微纳加工制成金属-PtTe_2-金属场效应晶体管,并进行了基于第Ⅱ类狄拉克半金属PtTe_2的场效应晶体管器件在太赫兹波段的光电流响应研究。该器件对太赫兹具有明显的光响应,响应度达到了3.85 A/W,等效噪声功率约为4.81 pW·Hz~(-1/2),其在低能尤其是太赫兹波段有着广泛的应用前景。