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Investigation of the coupling between the outer electrodes in the superconducting double-barrier devices

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Abstract

It is found experimentally that the critical current in the two-terminal double-barrier Nb/Ai-AlOx-Nb/Al-AlOx-Nb device is considerably larger than the critical current in the bottom junction of the Nb/Al-AlOx-Nb/Al-AlOx-Ta/Nb device of identical planar configuration produced in the same deposition run. Our data suggest that the origin of the phenomena is a direct Josephson coupling between the external electrodes rather than the inductive interaction between the junctions. (C) 1997 Elsevier Science B.V.

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... A double-barrier Josephson junction of a SIS'IS type is fabricated from Nb/Al-AlO -Nb/Al-AlO -Nb/Al structures deposited in the same vacuum with the aim to provide the identical material parameters of the films and the tunnel barriers. In the paper [16], the fabrication procedure is described more in detail. In the paper [2], an absolute value of a Josephson current in a double-barrier Josephson junction with very thin middle electrodes is studied experimentally. ...
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The dependence of the current density on the phase difference is investigated considering the layered superconducting structures of a SIS'IS type. To simplify the calculations, the quasiclassical equations for the Green's functions in a \textit{t}-representation are derived. An order parameter is considered as a piecewise constant function. To consider the general case, no restrictions on the dielectric layer transparency and the thickness of the intermediate layer are imposed. It was found that a new analytical expression for the current-phase relation can be used with the aim to obtain a number of previously known results arising in particular cases.
... A double-barrier Josephson junction of a SIS'IS type is fabricated from Nb/Al-AlO x -Nb/Al-AlO x -Nb/Al structures deposited in the same vacuum with the aim to provide the identical material parameters of the films and the tunnel barriers. In the paper [16], the fabrication procedure is described more in detail. In the paper [2], an absolute value of a Josephson current in a double-barrier Josephson junction with very thin middle electrodes is studied experimentally. ...
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The dependence of the current density on the phase difference is investigated considering the layered superconducting structures of a SIS’IS type. To simplify the calculations, the quasiclassical equations for the Green’s functions in a t-representation are derived. An order parameter is considered as a piecewise constant function. To consider the general case, no restrictions on the dielectric layer transparency and the thickness of the intermediate layer are imposed. It was found that a new analytical expression for the current-phase relation can be used with the aim to obtain a number of previously known results arising in particular cases.
... A similar dependence was obtained in works [12,13] on the basis of the classical Ohta model [14]. The experimental observation of a non-sinusoidal dependence of the current through a two-barrier superconductor junction was described in works [15,16]. ...
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