Origin of Ferromagnetism and its pressure and doping dependence in Tl₂Mn₂O₇

الأصل · EN

Using NMTO- downfolding technique, we explore and establish the origin of ferromagnetism in the pyrochlore system, Tl₂Mn₂O₇. It is found to be driven by hybridization induced spin-polarization of the delocalized charge carriers derived from Tl-s and O-p states. The mean-field estimate of the ferromagnetic transition temperature, Tc, estimated using computed exchange integrals are found to be in good agreement with the measurements. We find an enhancement of Tc for moderate doping with nonmagnetic Sb and a suppression of Tc upon application of pressure, both in agreement with experimental findings.