Two Types of Colossal Magnetoresistance in a Semiconducting Antiferromagnet
May 13, 2025
(a) Crystal structure of the Zintl compound Eu5In2As6. (b) Resistivity vs T, revealing both ‘upturn-type’ and ‘peak-type’ CMR. (c) Development of magnetic phase separation at low T. Magnetic domains of AFM-1 order onset below TN1 and phase separation of AFM-1 and AFM-0 domains is found below TN2.
Scientific Achievement
Neutron diffraction and bulk characterization measurements elucidate the possible origins of colossal magnetoresistance (CMR) in the semiconducting antiferromagnet Eu5In2As6.
Significance and Impact
CMR materials are important for many electronic, spintronic and caloritronic applications. Eu5In2As6 exhibits two different types of CMR with new, disparate mechanisms and therefore may pave the way for other CMR applications.
Research Details
- Both ‘peak-type’ CMR and ‘upturn-type’ CMR were identified in temperature-dependent resistivity measurements of Eu5In2As6.
- The ‘peak-type’ CMR is associated with magnetic polarons and the ‘upturn-type’ CMR is attributed to the melting of a charge-ordered state arising from magnetic phase separation.
“Two types of colossal magnetoresistance with distinct mechanisms in Eu5In2As6” Phys Rev B 111, 115114 (2025)
https://doi.org/10.1103/PhysRevB.111.115114
