Abdul Majid
Osaka University, Japan
Title: Tuning the properties of MoS2 monolayers using rare earth doping
Biography
Biography: Abdul Majid
Abstract
In post silicon era, the utilization of compound semiconductors (II-VI, III-V) has effectively fulfilled the technological requirements of modern age. The search of nanominiature and economical devices led the human curiosity to enter into the flatland of graphene in 2004 which opened gate to enormous prospects. The limitations of graphene due to its zero band gap motivated researchers to search for alternate two dimensional (2D) materials. Among recently focused 2D materials MoS2 is a prototype transition metal dichalcogenide due to its wide spread applications in devices and daily life.
This group is looking for efficient material design based on MoS2 monolayers to meet the requirements of future optoelectronics and spintronics devices. Our preliminary detailed computational investigations on MoS2 and CeS2 monolayers revealed that doping/alloying of rare earth (RE) elements modifies interlayer binding energy, defect formation energy and structural parameters of the layers which have strong influence on optical and magnetic properties of materials. Motivated by this we studied the effects of doping of series of RE elements (4f1 to 4f7) in MoS2 monolayers. The GGA-PBE calculations were performed using VASP code to relax the structures and calculate defect formation energy for all the materials. The spin polarization and long range ferromagnetic ordering was observed owing to 4f open shell configuration of the dopants. The analysis revealed dopant dependent band gap narrowing caused by appearance of impurity related states at edges of host bands. Most of the doped materials are p-type degenerate ferromagnetic semiconductors.