First-principles Study Of Magnetoresistance Of Layered Transition Metal Dichalcoginides

Two-dimensional materials have become a research focus in many fields,including chemistry,material and condensed matter physics,owing to their great potentials in various applications,such as electronics,optoelectronics,sensors,catalysis,gas separation and so on.Due to the excellent mechanical,electrical and optical properties,great efforts have been paid to layered transition metal dichalcoginides?TMDCs?in addition to graphene during the past 10 years.Very recently,tungsten telluride?WTe₂?are found to possess a non-saturated large magnetoresistance under low temperature and high magnetic field,which opens a new avenue of magnetic resistance.Based on density-functional theory,we systematically investigated the properties of two kinds of transition metal chalcogenide ReTaTe₄ and MoB₂X single-layer material.Through careful analysis of their electronic structures near Fermi level,ReTaTe₄ and MoB₂Te single layer are found to be good magnetic resistance materials.The main conclusions are summarized below:1.The electron carrier concentration and hole carrier concentration near the Fermi level of WTe₂ are found to be very sensitive to variation of lattice.By stretching lattice,the effect of temperature on the electronic structure is investigated.On this basis,layered ReTaTe₄ are further constructed by substitution of metal atoms of WTe₂,which are found to be a potential candidate with magnetoresistance.2.A class of layered materials,MoB₂X?X=S,Se and Te?gained by the substitution of Te atoms of WTe₂ are constructed to search for electronic materials with suitable"electrons and holes"matching.It is found that the number of electron and hole bands near the Fermi level are similar for MoB₂Te,indicating that MoB₂Te may possess excellent magnetic resistance performance.