Coherent vortex motion in superconductors

Grzegorz Jung

Superconducting quantum phase coherence gives rise to a variety of macroscopic quantum phenomena, among them to the Josephson effects. Due to extremely short coherence length, voltages appearing across high-TC superconducting microbridges are not related to Josephson effects but to the motion of current-created vortices. Josephson-like effects may however appear in relatively large high-TC bridges due to the coherence in current driven vortex flow. To enforce the coherent regime we employ laser written channels of easy vortex motion in c-axis oriented YBCO thin films, and heavy ion irradiated channels in BSCCO single crystals. The project is supported by the Israeli Science Foundation grant.
 

Figure 1: Schematic of the layout of bridge with laser written channel for easy vortex motion.	Figure 2: Magneto-optical image of field penetration into a laser written channel in the bridge constriction. Bright areas mark high magnetic field.

• Other active research projects, supported by four research grants, are opened for Ph.D. and M.S. students and include:
  • Dynamics of vortices in spatially restricted superconductors (Grzegorz Jung)
  • Anisotropy of flux-flow noise in vicinal YBCO thin films (Grzegorz Jung)
  • Intrinsic tunneling in colossal magnetoresistive materials (CMR) (Grzegorz Jung, Vladimir Markovich)
  • Metastable resistivity in CMR manganites (Grzegorz Jung, Gad Gorodetsky, Vladimir Markovich)
  • Local magnetic properties of CMR manganites. (Grzegorz Jung, Gad Gorodetsky, Vladimir Markovich).
  • Magnetic and transport noise in CMR manganites (Grzegorz Jung, Vladimir Markovich)
  • Current noise in quantum wells. (Grzegorz Jung)
  • Noise and plasmons enhanced charge separation in nanoparticles based devices. (Grzegorz Jung)
  • Ferromagnetic resonance and phase separation in bulk and nano-scale CMR materials (Evgeny Rosenberg, Alexander Shames, Gad Gorodetsky, Grzegorz Jung)
  • Transport, resonance and optical properties of carbon nanotubes filled with charge or magnetically ordered materials. (Evgeny Rosenberg, Grzegorz Jung)

Further details will be available soon at Prof. Jung's web site.