Magnetic-field dependence of the specific heat of YBa2Cu3O7

Abstract

Specific-heat measurements on ${\mathrm{YBa}}_2$ ${\mathrm{Cu}}_3$ ${\mathrm{O}}_7$ in magnetic fields to 7 T have shown the presence of Schottky anomalies with the field and temperature dependence expected for a fixed concentration of ${\mathrm{Cu}}^{2+}$ magnetic moments. The field-dependent part of the specific heat also includes a temperature-proportional contribution that is approximately proportional to field. These results are qualitatively different from those reported recently from another laboratory.