Giant Andreev Backscattering through a Quantum Point Contact Coupled via a Disordered Two-Dimensional Electron Gas to Superconductors

Journal Article · Wed Oct 01 00:00:00 EDT 1997 · Physical Review Letters

DOI:https://doi.org/10.1103/PhysRevLett.79.3250· OSTI ID:543870

den Hartog, S G; van Wees, B J; Klapwijk, T M ^[1]; Nazarov, Y V ^[2]; Borghs, G ^[3]

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1. Department of Applied Physics and Materials Science Center, University of Groningen, Nijenborgh 4, 9747 AG Groningen (The Netherlands)
2. Faculty of Applied Physics and Delft Institute for Microelectronics and Submicron Technology, Delft University of Technology, Lorentzweg 1, 2628 CJ Delft (The Netherlands)
3. Interuniversity Micro Electronics Center, Kapeldreef 75, B-3030 Leuven (Belgium)

We have investigated the superconducting-phase-modulated reduction in the resistance of a ballistic quantum point contact (QPC) connected via a disordered two-dimensional electron gas (2DEG) to superconductors. We show that this reduction is caused by coherent Andreev backscattering of holes through the QPC, which increases monotonically by reducing the bias voltage to zero. In contrast, the magnitude of the phase-dependent resistance of the disordered 2DEG displays a nonmonotonic reentrant behavior versus bias voltage. {copyright} {ital 1997} {ital The American Physical Society}

• OSTI ID: 543870
• Journal Information: Physical Review Letters, Vol. 79, Issue 17; Other Information: PBD: Oct 1997
• Country of Publication: United States
• Language: English

Related Subjects

66 PHYSICS
SUPERCONDUCTING JUNCTIONS
BACKSCATTERING
FLUX QUANTIZATION
INDIUM ARSENIDES
MAGNETORESISTANCE
NIOBIUM
ELECTRIC CONDUCTIVITY
COHERENT SCATTERING