TY - JOUR
T1 - Anomalous conductance quantization in the inter-band gap of a one-dimensional channel
AU - Green, Frederick
AU - Das, Mukunda P.
N1 - Publisher Copyright:
© 2018 IOP Publishing Ltd.
PY - 2018/9/3
Y1 - 2018/9/3
N2 - We report on a singular departure from the canonical step sequence of quantized conductance in a ballistic, quasi-one-dimensional metallic channel. Ideally in such a structure each sub-band population contributes its conductance quantum independently of the rest. In a picture based exclusively on coherent single-carrier transmission, unitary back-scattering may lower a conductance step below ideal but it is not possible for it to enhance it beyond the ideal conductance quantum. Precisely such an anomalous and robust voltage-dependent enhancement has already been observed over the whole density range between sub-band thresholds (de Picciotto R et al 2004 Phys. Rev. Lett. 92 036805, de Picciotto R et al 2008 J. Phys.: Condens. Matter 20 164204), a phenomenon left unexplained till now. We show theoretically that the anomalous enhancement of the ideal conductance is the hallmark of carrier transitions coupling the discrete sub-bands.
AB - We report on a singular departure from the canonical step sequence of quantized conductance in a ballistic, quasi-one-dimensional metallic channel. Ideally in such a structure each sub-band population contributes its conductance quantum independently of the rest. In a picture based exclusively on coherent single-carrier transmission, unitary back-scattering may lower a conductance step below ideal but it is not possible for it to enhance it beyond the ideal conductance quantum. Precisely such an anomalous and robust voltage-dependent enhancement has already been observed over the whole density range between sub-band thresholds (de Picciotto R et al 2004 Phys. Rev. Lett. 92 036805, de Picciotto R et al 2008 J. Phys.: Condens. Matter 20 164204), a phenomenon left unexplained till now. We show theoretically that the anomalous enhancement of the ideal conductance is the hallmark of carrier transitions coupling the discrete sub-bands.
KW - anomalous quantized conductance
KW - high-field phenomena in quantum channels
KW - interband dynamics in quantum channels
KW - non-linear mesoscopic transport
UR - http://www.scopus.com/inward/record.url?scp=85053380347&partnerID=8YFLogxK
U2 - 10.1088/1361-648X/aadafd
DO - 10.1088/1361-648X/aadafd
M3 - Article
SN - 0953-8984
VL - 30
JO - Journal of Physics Condensed Matter
JF - Journal of Physics Condensed Matter
IS - 38
M1 - 385304
ER -