Origin and evolution of surface spin current in topological insulators
Artikel i vetenskaplig tidskrift, 2018
The Dirac surface states of topological insulators offer a unique possibility for creating spin polarized charge currents due to the spin-momentum locking. Here we demonstrate that the control over the bulk and surface contribution is crucial to maximize the charge-to-spin conversion efficiency. We observe an enhancement of the spin signal due to surface-dominated spin polarization while freezin g out the bulk conductivity in semiconducting Bi1.5Sb0.5Te1.7Se1.3 below 100K. Detailed measurements up to room temperature exhibit a strong reduction of the magnetoresistance signal between 2and100K, which we attribute to the thermal excitation of bulk carriers and to the electron-phonon coupling in the surface states. The presence and dominance of this effect up to room temperature is promising for spintronic science and technology.
Författare
André Dankert
Chalmers, Mikroteknologi och nanovetenskap, Kvantkomponentfysik
Priyamvada Bhaskar
Student vid Chalmers
Dmitrii Khokhriakov
Chalmers, Mikroteknologi och nanovetenskap, Kvantkomponentfysik
Isabel Harrysson Rodrigues
Chalmers, Mikroteknologi och nanovetenskap, Mikrovågselektronik
Bogdan Karpiak
Chalmers, Mikroteknologi och nanovetenskap, Kvantkomponentfysik
Venkata Kamalakar Mutta
Uppsala universitet
Chalmers, Mikroteknologi och nanovetenskap, Kvantkomponentfysik
Sophie Charpentier
Chalmers, Mikroteknologi och nanovetenskap, Kvantkomponentfysik
Ion Garate
Université de Sherbrooke
Saroj Prasad Dash
Chalmers, Mikroteknologi och nanovetenskap, Kvantkomponentfysik
Physical Review B
2469-9950 (ISSN) 2469-9969 (eISSN)
Vol. 97 12 125414Ämneskategorier (SSIF 2011)
Materialkemi
Annan fysik
Den kondenserade materiens fysik
DOI
10.1103/PhysRevB.97.125414