TDPAC Spectroscopy

In the TDPAC laboratory of our division, time-differential perturbed angular correlation (TDPAC) technique is utilized for the studies of point defects, structural and magnetic phase transitions in metallic and inter-metallic systems, thin films and nano-crystalline materials. A four-detector TDPAC spectrometer with ultra fast BaF2 detectors has been developed for the above purpose. Highlights of the research carried out in the TDPAC lab include chemical transformation of crystalline hafnium tetrafluoride and thin films of hafnium dioxide. Dehydration pathway of HfF4.3H2O has been clearly established by this study. Thin films of HfO2 produced by pulsed laser deposition at various partial oxygen pressures have been studied to determine the nuclear quadrupole interaction (NQI) and presence of any ferromagnetism in HfO2 thin film. No indication of room-temperature ferromagnetism in HfO2 thin film was found.