Abstract
A fast time-domain magneto-optical technique is used to explore magnetic flux dynamics in the optically driven nonequilibrium state of Type I superconducting Pb films. It is found that the effective penetration of flux through the nonequilibrium intermediate state can be dramatically faster than through the normal metal. The system is probed through the application of rapid transient magnetic field pulses. Above the superconducting transition temperature, a direct measure of the diffusion coefficient of the magnetic field in the normal metal is obtained, on a time scale where the inhomogeneous spatial distribution of scattering sites is relevant. In the nonequilibrium superconductor the observations are dominated by coupling of the field transients to local motion of magnetic flux threading the normal domains. Studies as a function of how far the system is driven from equilibrium, and of the effect of a static applied magnetic field, indicate that the observations reflect the dynamics of normal/superconducting interfaces, and are strongly dependent on the microscopic arrangement of the intermediate state. By contrasting the response of pure Pb films to that of Pb1−xInx alloys, a comparison to Type II superconductivity is made.
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References
R.P. Huebener, “Magnetic Flux Structures in Superconductors”, Springer-Verlag, Berlin, 1979
L.D. Landau, Phys. Z. Sov. 11, 129 (1937)
G.J. Dolan, J. Low Temp. Phys. 15, 133 (1974)
D.J.E. Callaway, Nuc. Phys. B344, 627 (1990); Ann. Phys. (N.Y.) 213, 166 (1991)
L.R. Testardi, Phys. Rev. B 4, 2189 (1971)
K.E. Gray, ed., “Nonequilibrium Superconductivity, Phonons, and Kapitza Boundaries”, Plenum, New York, 1981
C.C. Chi, M.M.T. Loy, and D.C. Cronemeyer, Phys. Rev. B 23, 124 (1981); and C.C. Chi, private communication
Mark Johnson, Phys. Rev. Lett. 67, 374 (1991)
M.R. Freeman, R.R. Ruf, and R.J. Gambino, IEEE Trans. Mag. 27, 4840 (1991)
M.R. Freeman, Phys. Rev. Lett. 69, 1961 (1992)
H. Frahm, S. Ullah, and A.T. Dorsey, Phys. Rev. Lett. 66, 3067 (1991); F. Liu, M. Mondello, and N. Goldenfeld, ibid., p. 3071
M.R. Freeman, M.J. Brady, and J. Smyth, Appl. Phys. Lett. 60, 2555 (1992)
M.D. Maloney, F. de la Cruz, and M. Cardona, Phys. Rev. B 5, 3558 (1972)
L.D. Landau et al., “Electrodynamics of Continuous Media”, 2nd ed., Pergamon, Oxford, 1984, p. 201
P. Hammond, IEE Monograph 514S, 508 (1962)
S.B. Kaplan et al., Phys. Rev. B 14, 4854 (1976)
G.A. Sai-Halasz, C.C. Chi, A. Denenstein, and D.N. Langenberg, Phys. Rev. Lett. 33, 215 (1974)
V.F. Elesin and Yu. V. Kopaev, Sov. Phys. Usp. 24, 116 (1981)
See Ref. 1, p. 129
Because of pinning, the flux density in the probe region does not decay into equilibrium with the rest of the film during the long interval between pump pulses. In practice the field pulse amplitude is chopped at a frequency approximately half that of the laser pulse repetition, such that on average every pulse sequence toggles the system into a final state of different flux density than existed before that sequence.
A.B. Pippard, Phil. Mag. 41, 243 (1950)
R.J. Corruccini and J.J. Gniewek, N.B.S. Monograph 21, (1960)
X.-H. Hu, T. Juhasz, and W.E. Bron, Appl. Phys. A 52, 155 (1991)
Yu. V. Sharvin, Sov. Phys. JETP 6, 1031 (1958)
J.D. Livingston, Phys. Rev. 129, 1943 (1963)
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Freeman, M.R. Picosecond Studies of Nonequilibrium Flux Dynamics in Superconductors. MRS Online Proceedings Library 290, 323 (1992). https://doi.org/10.1557/PROC-290-323
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DOI: https://doi.org/10.1557/PROC-290-323