Abstract:
Measurements of the attenuation of longitudinal ultrasound in superconducting
UPt3 show a peak, below Hc2, which depends strongly
on the orientation of the field relative to the c axis. We propose an explanation of this
peak in terms of a vortex phase transition in an unconventional superconducting state, which
is consistent with recent neutron-scattering data.
Paper: [PDF]