Origin of the turn-on temperature behavior in WTe2
Y. L. Wang
L. R. Thoutam
Z. L. Xiao
J. Hu
S. Das
Z. Q. Mao
J. Wei
R. Divan
A. Luican-Mayer
G. W. Crabtree
W. K. Kwok
10027/21137
https://indigo.uic.edu/articles/journal_contribution/Origin_of_the_turn-on_temperature_behavior_in_WTe2/10774271
A hallmark of materials with extremely large magnetoresistance (XMR) is the transformative turn-on temperature behavior: when the applied magnetic field H is above certain value, the resistivity versus temperature ρ(T) curve shows a minimum at a field dependent temperature T∗, which has been interpreted as a magnetic-field-driven metal-insulator transition or attributed to an electronic structure change. Here, we demonstrate that ρ(T) curves with turn-on behavior in the newly discovered XMR material WTe2 can be scaled as MR∼(H/ρ0)m with m≈2 and ρ0 being the resistivity at zero field. We obtained experimentally and also derived from the observed scaling the magnetic field dependence of the turn-on temperature T∗∼(H-Hc)ν with ν≈1/2, which was earlier used as evidence for a predicted metal-insulator transition. The scaling also leads to a simple quantitative expression for the resistivity ρ∗≈2ρ0 at the onset of the XMR behavior, which fits the data remarkably well. These results exclude the possible existence of a magnetic-field-driven metal-insulator transition or significant contribution of an electronic structure change to the low-temperature XMR in WTe2. This work resolves the origin of the turn-on behavior observed in several XMR materials and also provides a general route for a quantitative understanding of the temperature dependence of MR in both XMR and non-XMR materials.
2016-09-12 00:00:00
turn-on temperature behavior
temperature
WTe2
origin