Extremely large magnetoresistance and ultrahigh mobility in the topological Weyl semimetal NbP

TL;DR

This paper reports that NbP, a topological Weyl semimetal, exhibits extremely large magnetoresistance and ultrahigh mobility, demonstrating unique transport properties due to its combined topological and normal semimetal characteristics.

Contribution

It provides the first detailed magneto-transport study of NbP, revealing its exceptional magnetoresistance and mobility, highlighting the interplay of topological and conventional phases.

Findings

Magnetoresistance of 850,000% at 1.85 K in 9 T

Room temperature magnetoresistance of 250%

Carrier mobility of 5×10^6 cm^2 V^-1 s^-1

Abstract

Recent experiments have revealed spectacular transport properties of conceptually simple semimetals. For example, normal semimetals (e.g. WTe$_2$) have started a new trend to realize a large magnetoresistance, which is the change of electrical resistance by an external magnetic field. Weyl semimetal (WSM) is a topological semimetal with massless relativistic electrons as the three-dimensional analogue of graphene and promises exotic transport properties and surface states, which are different from those of the famous topological insulators (TIs). In this letter, we choose to utilize NbP in magneto-transport experiments because its band structure is on assembly of a WSM and a normal semimetal. Such a combination in NbP indeed leads to the observation of remarkable transport properties, an extremely large magnetoresistance of 850,000 % at 1.85 K (250 % at room temperature) in a magnetic field of 9 T without any signs of saturation, and ultrahigh carrier mobility of 5$\times$10$^6$ cm$^2$ V$^{-1}$ s$^{-1}$ accompanied by strong Shubnikov-de Hass (SdH) oscillations. NbP presents a unique example to consequent design the functionality of materials by combining the topological and conventional phases.