Oral: Pseudo Jahn-Teller effect at the intrinsic defects in hexagonal boron nitride

Since the 2016 discovery of defect-based quantum emitters in hexagonal boron nitride (hBN), significant theoretical and experimental efforts have been directed towards identifying their chemical nature(s). Most of the theoretical works themselves focus on the high-symmetry reference structures for these defects and have not considered the possibility of the pseudo Jahn-Teller effect (PJTE), which arises from the vibronic coupling between the ground state and excited states. Using density functional theory-based calculations, we explore the effects of pseudo Jahn-Teller distortion on the structural, electronic and optical properties of intrinsic defects in hBN. Using intrinsic defects as prototype defects, we demonstrate the consequences of PJTE on the observable properties of the defects and show that one cannot rule out PJTE at the defects a priori.