五鎢化六氮之磁傳輸

Abstract

本文主要研究過度金屬氮化物五鎢化六氮(W5N6)奈米薄膜在低溫下的電性與磁性傳輸。系統在溫度小/等於30 K以下，主要以變程躍遷導電為主，並顯示出明顯的絕緣性質。而在磁場的影響下，隨著磁場由小到大會呈現由負到正的磁阻變化關係，而且變化隨著溫度上升而被減弱。另外系統在外加垂直與平行磁場下，磁阻顯示出相對較弱的各向異性。在低溫下，我們還在材料中發現明顯的磁滯，不過磁滯只有在特定的溫度區間存在，相對高溫與相對低溫都會減弱其效應。

We study the transport properties of the transition metal nitride W5N6 thin film at low temperatures. This material behaves as an insulator when the temperature is below 30 K, and the transport is dominated by variable range hopping (VRH) conduction. Under the influence of a magnetic field, the resistance transitions from negative to positive magnetoresistance with increasing magnetic field. This effect diminishes as the temperature rises. We also noticed that the magnetoresistance anisotropy of the material is relatively weak when subjected to both perpendicular and parallel magnetic fields. Moreover, we observed significant magnetic hysteresis in the material at low temperatures. The hysteresis effect is only present within specific temperature ranges and is weakened at relatively high and low temperatures.