Open AccessTwo distinctive regimes in the charge transport of a magnetic topological ultra thin film
Author(s) -
Amir Sabzalipour,
Moslem Mir,
M. Zarenia,
B. Partoens
Publication year - 2020
Publication title -
new journal of physics
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.584
H-Index - 190
ISSN - 1367-2630
DOI - 10.1088/1367-2630/abc989
Subject(s) - physics , condensed matter physics , electron , topological insulator , thermal conduction , isotropy , charge (physics) , anisotropy , charge carrier , impurity , boltzmann constant , dissipative system , relaxation (psychology) , topological quantum number , topology (electrical circuits) , quantum mechanics , mathematics , combinatorics , psychology , social psychology
The effect of the magnetic impurities on the charge transport in a magnetic topological ultra-thin film (MTF) is analytically investigated by applying the semi-classical Boltzmann framework through a modified relaxation-time approximation. Our results for the relaxation time of electrons as well as the charge conductivity of the system exhibit two distinct regimes of transport. We show that the generated charge current in a MTF is always dissipative and anisotropic when both conduction bands are involved in the charge transport. The magnetic impurities induce a chirality selection rule for the transitions of electrons which can be altered by changing the orientation of the magnetic impurities. On the other hand, when a single conduction band participates in the charge transport, the resistivity is isotropic and can be entirely suppressed due to the corresponding chirality selection rule. Our findings propose a method to determine an onset thickness at which a crossover from a three-dimensional magnetic topological insulator to a (two-dimensional) MTF occurs.