Time-resolved infrared spectroscopy of superconducting NbTiN film near H$_{c2}$

ORAL

Abstract

We use subnanoseconds time-resolved, pump-probe infrared spectroscopy to study vortex dynamics of a conventional superconductor, Nb$_{0.5}$Ti$_{0.5}$N near H$_{c2}$. The measurements were performed at the National Synchrotron Light Source, Brookhaven National Laboratory; Picosecond pulses from a near-infrared Ti:sapphire laser were used as a pump and, subnanosecond pulses of infrared synchrotron radiation as a probe. We report detailed magnetic field dependences of the amplitude of photoinduced quasiparticles and the effective lifetime of the quasiparticles and also discuss vortex dynamics in the system near H$_{c2}$. Near H$_{c2}$, we observe an interesting deviation from the field-independent behavior of the effective lifetime at lower fields.

*The research has been supported by the DOE through grant DE-FG02-02ER45984 at Florida and contract DE-AC02-98CH10886 at BNL.

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Authors

  • Jungseek Hwang

    • University of Florida

  • Haidong Zhang

    • University of Nebraska

  • David H. Reitze

    • Physics Dept., University of Florida
    • University of Florida

  • Christopher J. Stanton

    • University of Florida

  • David B. Tanner

    • Univ of Florida, Dept of Phys
    • Dept of Physics, University of Florida
    • University of Florida

  • G. L. Carr

    • Brookhaven National Laboratory
    • Brookhaven National Laboratory, National Synchrontron Light Source