Abstract:
Spintronics devices, integral to modern technology, allow for the manipulation of both
charge carriers and spin within a single platform, offering advantages such as non-volatility,
rapid data processing, low power consumption, and high integration density. To exploit
these benefits, semiconductor materials must be doped with magnetic impurities, typically
transition metals, to create diluted magnetic semiconductors (DMS) with combined ferro
magnetic and semiconductor characteristics. This thesis investigates the theoretical impact
of temperature, dopant concentration, and magnon-exciton interaction on the magnetic
properties of manganese-doped DMS materials, specifically focusing on manganese-doped
GaMnAs. Employing the equation of motion approach within Green’s function formalism, a
Heisenberg-type model Hamiltonian incorporating the interaction of magnons and excitons
was developed and solved. Theoretical expressions linking magnon number and system mag
netization to temperature, dopant concentration (with specific values of x = 0.03,0.04,0.05),
and magnon-exciton coupling strength (with values of 0.3,0.4,0.5) were derived from the
spectral representation of the obtained Green’s function. Our findings indicate that the
total number of magnons increases with temperature and the strength of magnon-exciton
coupling, while decreasing with higher dopant concentrations. System magnetization dimin
ishes with increasing temperature but is boosted by higher dopant concentrations, leading to
higher ferromagnetic critical temperatures. Moreover, an escalation in the strength of the
magnon-exciton interaction suppresses system magnetization. This research enhances our
understanding of the intricate dynamics governing DMS materials, offering valuable insights
for the advancement of spintronics technology
