Gate-tunable superconducting weak link behavior in top-gated LaAlO{sub 3}-SrTiO{sub 3}

Journal Article · Mon May 25 04:00:00 EDT 2015 · Applied Physics Letters

DOI:https://doi.org/10.1063/1.4921924· OSTI ID:22402496

Bal, V. V.; Mehta, M. M.; Chandrasekhar, V. ^[1]; Ryu, S.; Lee, H.; Folkman, C. M.; Eom, C. B. ^[2]

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1. Department of Physics and Astronomy, Northwestern University, Evanston, Illinois 60208 (United States)
2. Department of Materials Science and Engineering, University of Wisconsin-Madison, Madison, Wisconsin 53706 (United States)

We use a combination of global back-gating and local top-gating to define nanoscale devices in the two-dimensional electron gas at the LaAlO{sub 3}-SrTiO{sub 3} interface, demonstrating an efficient way for much finer spatial control over the properties of the interface, as compared to back-gating alone. The devices show indications of an inhomogenous superconducting weak link. The variation of critical current with perpendicular magnetic field shows evidence of oscillations, which hints at Josephson coupling. The variation of the critical current and zero bias resistance with temperature is consistent with short, overdamped weak links. We show that the applied top-gate voltage provides a strong handle on the properties of these weak links. This technique can be an important tool to define a variety of device structures in this system, allowing us to probe the nature of superconductivity in the LaAlO{sub 3}-SrTiO{sub 3} interface system in different ways.

• OSTI ID: 22402496
• Journal Information: Applied Physics Letters, Journal Name: Applied Physics Letters Journal Issue: 21 Vol. 106; ISSN APPLAB; ISSN 0003-6951
• Country of Publication: United States
• Language: English

Related Subjects

71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
ALUMINATES
ELECTRON GAS
JOSEPHSON EFFECT
LANTHANUM COMPOUNDS
MAGNETIC FIELDS
NANOSTRUCTURES
OSCILLATIONS
STRONTIUM TITANATES
SUPERCONDUCTIVITY