Abstract
We present a study on low-Tc superconductor-insulator-ferromagnet-superconductor (SIFS) Josephson junctions. SIFS junctions have gained considerable interest in recent years because they show a number of interesting properties for future classical and quantum computing devices. We optimized the fabrication process of these junctions to achieve a homogeneous current transport, ending up with high-quality samples. Depending on the thickness of the ferromagnetic layer and on temperature, the SIFS junctions are in the ground state with a phase drop of either 0 or π. By using a ferromagnetic layer with variable step-like thickness along the junction, we obtained a so-called 0–π Josephson junction, in which 0 and π ground states compete with each other. At a certain temperature the 0 and π parts of the junction are perfectly symmetric, i.e. the absolute critical current densities are equal. In this case the degenerate ground state corresponds to a vortex of supercurrent circulating clock- or counterclockwise and creating a magnetic flux which carries a fraction of the magnetic flux quantum Φ0.
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References
L. Bulaevskii, V. Kuzii, A. Sobyanin, JETP Lett. 25, 7 (1977)
A.V. Veretennikov, V.V. Ryazanov, V.A. Oboznov, A.Y. Rusanov, V.A. Larkin, J. Aarts, Physica B 284, 495 (2000)
T. Kontos, M. Aprili, J. Lesueur, X. Grison, Phys. Rev. Lett. 89, 137007 (2002)
M. Weides, M. Kemmler, E. Goldobin, D. Koelle, R. Kleiner, H. Kohlstedt, A. Buzdin, Appl. Phys. Lett. 89, 122511 (2006)
L.N. Bulaevskii, V.V. Kuzii, A.A. Sobyanin, Solid State Commun. 25, 1053 (1978)
E. Goldobin, D. Koelle, R. Kleiner, Phys. Rev. B 66, 100508 (2002)
J.R. Kirtley, K.A. Moler, D.J. Scalapino, Phys. Rev. B 56, 886 (1997)
J.R. Kirtley, C.C. Tsuei, M. Rupp, J.Z. Sun, L.S. Yu-Jahnes, A. Gupta, M.B. Ketchen, K.A. Moler, M. Bhushan, Phys. Rev. Lett. 76, 1336 (1996)
H. Hilgenkamp, Ariando, H.J.H. Smilde, D.H.A. Blank, G. Rijnders, H. Rogalla, J.R. Kirtley, C.C. Tsuei, Nature 422, 50 (2003)
R. Gross, D. Koelle, Rep. Prog. Phys. 57, 651 (1994)
E. Goldobin, A. Sterck, T. Gaber, D. Koelle, R. Kleiner, Phys. Rev. Lett. 92, 057005 (2004)
J.R. Kirtley, C.C. Tsuei, K.A. Moler, Science 285, 1373 (1999)
A. Sugimoto, T. Yamaguchi, I. Iguchi, Physica C 367, 28 (2002)
S.M. Frolov, D.J. Van Harlingen, V.V. Bolginov, V.A. Oboznov, V.V. Ryazanov, Phys. Rev. B 74, 020503 (2006)
M.L. Della Rocca, M. Aprili, T. Kontos, A. Gomez, P. Spatkis, Phys. Rev. Lett. 94, 197003 (2005)
M. Weides, M. Kemmler, H. Kohlstedt, R. Waser, D. Koelle, R. Kleiner, E. Goldobin, Phys. Rev. Lett. 97, 247001 (2006)
M. Weides, K. Tillmann, H. Kohlstedt, Physica C 437–438, 349 (2006)
M. Gurvitch, M.A. Washington, H.A. Huggins, J.M. Rowell, IEEE Trans. Magn. 19, 791 (1983)
M. Weides, C. Schindler, H. Kohlstedt, J. Appl. Phys. 101, 063902 (2007)
V.A. Oboznov, V.V. Bol’ginov, A.K. Feofanov, V.V. Ryazanov, A.I. Buzdin, Phys. Rev. Lett. 96, 197003 (2006)
M. Weides, H. Kohlstedt, J. Pfeiffer, M. Kemmler, D. Koelle, R. Kleiner, E. Goldobin, in preparation
T. Yamashita, K. Tanikawa, S. Takahashi, S. Maekawa, Phys. Rev. Lett. 95, 097001 (2005)
T. Yamashita, S. Takahashi, S. Maekawa, Appl. Phys. Lett. 88, 132501 (2006)
E. Goldobin, K. Vogel, O. Crasser, R. Walser, W.P. Schleich, D. Koelle, R. Kleiner, Phys. Rev. B 72, 54527 (2005)
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74.50.+r; 74.78.Fk; 74.81.-g; 85.25.Cp
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Weides, M., Kohlstedt, H., Waser, R. et al. Ferromagnetic 0–π Josephson junctions. Appl. Phys. A 89, 613–617 (2007). https://doi.org/10.1007/s00339-007-4206-3
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DOI: https://doi.org/10.1007/s00339-007-4206-3