Tuning the Conductance of Dirac Fermions on the Surface of a Topological Insulator
Data(s) |
29/01/2010
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Resumo |
We study the transport properties of the Dirac fermions with a Fermi velocity v(F) on the surface of a topological insulator across a ferromagnetic strip providing an exchange field J over a region of width d. We show that the conductance of such a junction, in the clean limit and at low temperature, changes from oscillatory to a monotonically decreasing function of d beyond a critical J. This leads to the possible realization of a magnetic switch using these junctions. We also study the conductance of these Dirac fermions across a potential barrier of width d and potential V-0 in the presence of such a ferromagnetic strip and show that beyond a critical J, the criteria of conductance maxima changes from chi = eV(0)d/(h) over barv(F) = n pi to chi = (n + 1/2)pi for integer n. We point out that these novel phenomena have no analogs in graphene and suggest experiments which can probe them. |
Formato |
application/pdf |
Identificador |
http://eprints.iisc.ernet.in/25783/1/e046403.pdf Mondal, S and Sen, D and Sengupta, K and Shankar, R (2010) Tuning the Conductance of Dirac Fermions on the Surface of a Topological Insulator. In: Physical Review Letters, 104 (4). |
Publicador |
The American Physical Society |
Relação |
http://prl.aps.org/abstract/PRL/v104/i4/e046403 http://eprints.iisc.ernet.in/25783/ |
Palavras-Chave | #Centre for High Energy Physics |
Tipo |
Journal Article NonPeerReviewed |