On the self-consistent theory of Josephson effect in ballistic superconducting microconstrictions

• Veröffentlicht in: Физика низких температур
• Datum: 1999
• Hauptverfasser: Zareyan, M., Kolesnichenko, Yu.A., Omelyanchouk, A.N.
• Format: Artikel
• Sprache: Englisch
• Veröffentlicht: Фізико-технічний інститут низьких температур ім. Б.І. Вєркіна НАН України 1999
• Schlagworte: Свеpхпpоводимость, в том числе высокотемпеpатуpная
• Online Zugang: https://nasplib.isofts.kiev.ua/handle/123456789/139331
• Назва журналу: Digital Library of Periodicals of National Academy of Sciences of Ukraine
• Zitieren: On the self-consistent theory of Josephson effect in ballistic superconducting microconstrictions / M. Zareyan, Yu.A. Kolesnichenko, A.N. Omelyanchouk // Физика низких температур. — 1999. — Т. 25, № 11. — С. 1154-1160. — Бібліогр.: 14 назв. — англ.

The microscopic theory of current-carrying states in the ballistic superconducting microchannel is presented. The effects of the contact length L on the Josephson current are investigated. For the temperatures T close to the critical temperature Tc the problem is treated self-consistently, with allowance for the distribution of the order parameter D(r) inside the contact. The closed integral equation for D in strongly inhomogeneous microcontact geometry (L< and ~x₀ , where x₀ is the coherence length at T=0) replaces the differential Ginzburg-Landau equation. The critical current Ic(L) is expressed in terms of the solution of this integral equation. The limiting cases of L<<x₀ and L>>x₀ are considered. With increasing length L, the critical current decreases, although the ballistic Sharvin resistance of the contact remains the same as at L=0. For ultrashort channels with L< and ~ aD (aD~nF/wD , where w D is the Debye frequency) the corrections for the value of the critical current Ic(L=0) are sensitive to the strong-coupling effects.