PHOTOACOUSTIC AND PHOTOPYROELECTRIC INVESTIGATION OF THE ANTIFERROMAGNETS COO AND CR2O3 IN THE NEIGHBORHOOD OF THE NEEL TEMPERATURE

The critical behaviour of the dynamic and static thermal properties are investigated in the neighbourhood of the Neel temperature of single crystal antiferromagnetic CoO and Cr2O3 Photoacoustic front and pyroelectric rear detection of front illumination induced temperature oscillations are used to determine critical exponents and amplitudes of the specific heat capacity anomaly. Simultaneously measured thermal conductivity data are also presented.