Magnetic properties of the David star in the 2D-Kagome lattice

ABSTRACT

We investigate the magnetisation and internal energy of the David star in the Kagome lattice by the effective field theory developed by Kaneyoshi. First-order, Second-order and successive phase transitions are observed for different spin-down orientations. Spin-down orientation of identical atoms causes a second-order phase transition, spin-down orientation of different atoms causes a first-order and successive phase transitions. Minimum internal energy is obtained as U_{David star}=−5 for all spin-up orientations, whereas it increases (U_{David star}> −5) for at least one spin-down orientation. For spin-down orientation of A↑–A↓, internal energy becomes zero at a certain temperature and we call this temperature ‘zero internal energy temperature (Tzie)’. At T < Tzie=1.99, internal energy is positive, whereas it is negative for other spin states. Therefore, spin-induced minimum internal energy broken is observed except for all spin-up (A↑, B↑ and C↑) cases.

KEYWORDS:

• Frustrated material
• Kagome lattice
• David star
• spin
• magnetism
• effective field theory

Disclosure statement

No potential conflict of interest was reported by the author(s).