Transport entropy of vortex motion inYBa2Cu3O7

We report measurements of entropy transport due to vortex motion in single-cyrstal ${\mathrm{YBa}}_{2}$${\mathrm{Cu}}_{3}$${\mathrm{O}}_{7}$. From these magnetothermal measurements we are able to determine thermodynamic properties, such as the transport line energy and superconducting phase boundary ${\mathit{T}}_{\mathit{c}}$(H), as well as transport parameters associated with flux motion. Below ${\mathit{T}}_{\mathit{c}}$, the data are compared with the microscopic theory of Caroli and Maki. Interestingly, we also find entropy transport in the fluctuation regime above ${\mathit{T}}_{\mathit{c}}$, which grows with applied field and for which no theory exists.