Insulating state and giant nonlocal response in an InAs/GaSb quantum well in the quantum Hall regime.
We present transport measurements performed in InAs/GaSb double quantum wells. At the electron-hole crossover tuned by a gate voltage, a strong increase in the longitudinal resistivity is observed with increasing perpendicular magnetic field. Concomitantly with a local resistance exceeding the resistance quantum by an order of magnitude, we find a pronounced nonlocal resistance signal of almost similar magnitude. The coexistence of these two effects is reconciled in a model of counterpropagating and dissipative quantum Hall edge channels providing backscattering, shorted by a residual bulk conductivity.
Solid State Physics Laboratory, ETH Zürich, 8093 Zürich, Switzerland.
Fabrizio
F
Nichele
Solid State Physics Laboratory, ETH Zürich, 8093 Zürich, Switzerland.
Atindra Nath
AN
Pal
Solid State Physics Laboratory, ETH Zürich, 8093 Zürich, Switzerland.
Patrick
P
Pietsch
Solid State Physics Laboratory, ETH Zürich, 8093 Zürich, Switzerland.
Thomas
T
Ihn
Solid State Physics Laboratory, ETH Zürich, 8093 Zürich, Switzerland.
Klaus
K
Ensslin
Solid State Physics Laboratory, ETH Zürich, 8093 Zürich, Switzerland.
Christophe
C
Charpentier
Solid State Physics Laboratory, ETH Zürich, 8093 Zürich, Switzerland.
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