ISSN:
1077-3118
Source:
AIP Digital Archive
Topics:
Physics
Notes:
It is demonstrated that at 4.2 K the critical current Ic of a superconducting Nb micro (μ) bridge (typical thickness 30 nm, length 200 μm, width 10 μm) can be reversibly varied over a wide range by applying electrical fields of the order of 108 V/m at an insulated gate prepared on top of the Nb μbridge. The preparation and the electrical characteristics of these metal/insulator/superconductor field effect transistor-like devices of the type M/NbOx/Nb, where M represents Al, Au, or Nb gate metals, are described. Additional experiments in external magnetic fields revealed that the gate-controlled effect on Ic is based on depinning due to an electric field-induced ‘quasimetallic' state of the typically 10-nm-thick NbOx. Under optimized conditions, a gate power of less than 200 μW is needed to switch the superconducting Nb μbridge into the normal conducting state.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1063/1.111405
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