Physics – Condensed Matter – Superconductivity
Scientific paper
2004-10-29
Modern Physics Letters B 18, 1205 (2004)
Physics
Condensed Matter
Superconductivity
brief review, 10 pages, 11 figures
Scientific paper
10.1142/S0217984904007785
The gap function in unconventional superconductors may vanish at points or lines in momentum space, permitting electronic excitations, termed nodal quasiparticles, to exist at temperatures well below the superconducting transition. In the vortex phase, the presence of nodal quasiparticles should be directly observable through the variation of the heat capacity with the angle between a magnetic field and the location of the zeroes of the gap. The heat capacity of candidate non-magnetic unconventional superconductors Lu(Y)Ni2B2C were found to exhibit fourfold oscillations with field angle, the first such observation. The observed angular variations are in quantitative agreement with theory, confirming that quasiparticles are created via Doppler shifts at nodes along <100>. Anomalous disorder effects have been also observed in the field-angle dependent heat capacity C_{p}(\alpha). In a slightly disordered sample, anomalous secondary minima along <110> appeared for \mu_{0}H > 1 T, leading to an eightfold pattern. The coexistence of an anisotropic superconducting gap and nonlocal effects is shown to drive the anomalous behavior. These results demonstrate that field-angle-dependent heat capacity can be a powerful tool in probing the momentum-space gap structure in unconventional superconductors such as high T_{c} cuprates, heavy fermions, borocarbides, etc.
Park Tuson
Salamon Myron B.
No associations
LandOfFree
Study on Unconventional Superconductors via Angle-resolved Specific Heat does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Study on Unconventional Superconductors via Angle-resolved Specific Heat, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Study on Unconventional Superconductors via Angle-resolved Specific Heat will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-511117