Magnetic flux noise in the three Josephson junctions superconducting ring

• Published in: Физика низких температур
• Date: 2008
• Main Authors: Il’ichev, E., Omelyanchouk, A.N.
• Format: Article
• Language: English
• Published: Фізико-технічний інститут низьких температур ім. Б.І. Вєркіна НАН України 2008
• Subjects: Свеpхпpоводимость, в том числе высокотемпеpатуpная
• Online Access: https://nasplib.isofts.kiev.ua/handle/123456789/116976
• Journal Title: Digital Library of Periodicals of National Academy of Sciences of Ukraine
• Cite this: Magnetic flux noise in the three Josephson junctions
 superconducting ring
 / E. Il’ichev, A.N. Omelyanchouk // Физика низких температур. — 2008. — Т. 34, № 6. — С. 520–524. — Бібліогр.: 11 назв. — англ.

We analyze the influence of noise on magnetic properties of a superconducting loop which contains three
 Josephson junctions. This circuit is a classical analog of a persistent current (flux) qubit. A loop supercurrent
 induced by external magnetic field at the presence of thermal fluctuations is calculated. In order to
 get connection with experiment we calculate the impedance of the low-frequency tank circuit which is inductively
 coupled with a loop of interest. We compare obtained results with the results in quantum mode —
 when the three junction loop exhibits quantum tunneling of the magnetic flux. We demonstrate that the
 tank-loop impedance in the classical and quantum modes have different temperature dependence and can be
 easily distinguished experimentally.