2012/10/19 by Hai-Feng Li, Haifeng Li, Yinguo Xiao +9 · 1 citation
Materials Science · Physics and Astronomy · #Advanced Condensed Matter Physics #Anisotropy #Antiferromagnetism #Condensed matter physics #Electron #Magnetic and transport properties of perovskites and related materials #Magnetic field #Magnetism #Magnetoresistance #Materials science #Physics #Polaron #Quantum mechanics #Spin (aerodynamics) #Spins #Thermal Expansion and Ionic Conductivity #cond-mat.mtrl-sci #cond-mat.str-el #cond-mat.supr-con
paper · pdf · doi:10.1038/srep00750
published as Scientific Reports 2, Article number: 750, 2012
openalex publication_date 2012/10/19 · arxiv created 2015/02/03 · arxiv updated 2015/02/04 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
Magnetoresistance (MR) has attracted tremendous attention for possible technological applications. Understanding the role of magnetism in manipulating MR may in turn steer the searching for new applicable MR materials. Here we show that antiferromagnetic (AFM) GdSi metal displays an anisotropic positive MR value (PMRV), up to ~415%, accompanied by a large negative thermal volume expansion (NTVE). Around T(N) the PMRV translates to negative, down to ~-10.5%. Their theory-breaking magnetic-field dependencies [PMRV: dominantly linear; negative MR value (NMRV): quadratic] and the unusual NTVE indicate that PMRV is induced by the formation of magnetic polarons in 5d bands, whereas NMRV is possibly due to abated electron-spin scattering resulting from magnetic-field-aligned local 4f spins. Our results may open up a new avenue of searching for giant MR materials by suppressing the AFM transition temperature, opposite the case in manganites, and provide a promising approach to novel magnetic and electric devices.