International Workshop on Physics with Positrons at Jefferson Lab (JPos17)

Positron studies of origin of novel electronic phenomena in complex oxides

Not scheduled

15m

Room F113 (CEBAF Center)

Poster

Speaker

Ms Pooneh Saadatkia (Bowling Green State University)

Description

Complex oxides with the ABO3 perovskite crystal structure reveal a range of spectacular phenomena such as superconductivity, ferroelectricity, and metal-insulator transitions. SrTiO3, has been the focus of intense research in the world of oxide materials due to its functional, dielectric and ferroelectric properties. Vacancies are usually suggested to be the dominant point defects in perovskite oxides which significantly affect the material properties. Therefore, identifying the nature of vacancy defects is crucial to understand the origin of novel phenomena in complex oxides such as room temperature persistent [PRL 111, 187403 (2013)], and transient photoconductivity in bulk single crystals of STO, also unusual thermo-luminescence and photoluminescence behavior of STO during phase transition. This can be achieved using Positron annihilation lifetime spectroscopy (PALS) which is an excellent technique to identify vacancy-related point defects in materials on atomic scale. PALS and digital coincidence Doppler broadening spectroscopy have been applied to examine the presence of defects and their role in room temperature photoconductivity of bulk STO single crystals.