TY - JOUR
T1 - Zero-field edge plasmons in a magnetic topological insulator
AU - Mahoney, Alice C.
AU - Colless, James I.
AU - Peeters, Lucas
AU - Pauka, Sebastian J.
AU - Fox, Eli J.
AU - Kou, Xufeng
AU - Pan, Lei
AU - Wang, Kang L.
AU - Goldhaber-Gordon, David
AU - Reilly, David J.
N1 - Funding Information:
We thank Andrew Doherty and David DiVincenzo for useful conversations. Device fabrication and preliminary characterisation was supported by the Department of Energy, Office of Science, Basic Energy Sciences, Materials Sciences and Engineering Division, under Contract DE-AC02-76SF00515. Microwave and transport measurements presented in the main text were supported by Microsoft Research, the Army Research Office grant W911NF-14-1-0097, the Australian Research Council Centre of Excellence Scheme (Grant No. EQuS CE110001013). Materials growth was supported by the DARPA MESO program under Contracts No. N66001-12-1-4034 and No. N66001-11-1-4105. Infrastructure and cryostat support were funded in part by the Gordon and Betty Moore Foundation through Grant GBMF3429. E.J.F. acknowledges support from a DOE Office of Science Graduate Fellowship. L.P. was supported by a Stanford Graduate Fellowship.
Publisher Copyright:
© 2017 The Author(s).
PY - 2017/12/1
Y1 - 2017/12/1
N2 - Incorporating ferromagnetic dopants into three-dimensional topological insulator thin films has recently led to the realisation of the quantum anomalous Hall effect. These materials are of great interest since they may support electrical currents that flow without resistance, even at zero magnetic field. To date, the quantum anomalous Hall effect has been investigated using low-frequency transport measurements. However, transport results can be difficult to interpret due to the presence of parallel conductive paths, or because additional non-chiral edge channels may exist. Here we move beyond transport measurements by probing the microwave response of a magnetised disk of Cr-(Bi,Sb)2Te3. We identify features associated with chiral edge plasmons, a signature that robust edge channels are intrinsic to this material system. Our results provide a measure of the velocity of edge excitations without contacting the sample, and pave the way for an on-chip circuit element of practical importance: the zero-field microwave circulator.
AB - Incorporating ferromagnetic dopants into three-dimensional topological insulator thin films has recently led to the realisation of the quantum anomalous Hall effect. These materials are of great interest since they may support electrical currents that flow without resistance, even at zero magnetic field. To date, the quantum anomalous Hall effect has been investigated using low-frequency transport measurements. However, transport results can be difficult to interpret due to the presence of parallel conductive paths, or because additional non-chiral edge channels may exist. Here we move beyond transport measurements by probing the microwave response of a magnetised disk of Cr-(Bi,Sb)2Te3. We identify features associated with chiral edge plasmons, a signature that robust edge channels are intrinsic to this material system. Our results provide a measure of the velocity of edge excitations without contacting the sample, and pave the way for an on-chip circuit element of practical importance: the zero-field microwave circulator.
UR - http://www.scopus.com/inward/record.url?scp=85036564686&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85036564686&partnerID=8YFLogxK
U2 - 10.1038/s41467-017-01984-5
DO - 10.1038/s41467-017-01984-5
M3 - Article
C2 - 29184065
AN - SCOPUS:85036564686
VL - 8
JO - Nature Communications
JF - Nature Communications
SN - 2041-1723
IS - 1
M1 - 1836
ER -