Effects of site dilution on the magnetic properties of geometrically frustrated antiferromagnets

Abstract

The effect of site dilution by non magnetic impurities on the susceptibility of geometrically frustrated antiferromagnets (kagome and pyrochlore lattices) is discussed in the framework of the Generalized Constant Coupling model, for both classical and quantum Heisenberg spins. For the classical diluted pyrochlore lattice, excellent agreement is found when compared with Monte Carlo data. Results for the quantum case are also presented and discussed.

Susceptibility and dilution effects of the kagomé bilayer geometrically frustrated network: A Ga NMR study ofSrCr9pGa12−9pLimot1, Mendels2, Collin3 et al. 2002Phys. Rev. B84121020View full textAdd to dashboardCite

“…Also, the nonrandom distribution of the nonmagnetic vacancies in SCGO's kagomé bilayer might induce quantitative differences between the calculated and experimental susceptibilities, as pointed out in Ref. 52. The general picture drawn by our overview of the experimental and theoretical data is that even short-range spin-spin correlations clearly play a major role in SCGO, or more generally in all geometrically frustrated compounds.…”

Spin Ice State in Frustrated Magnetic Pyrochlore Materials

“…At a theoretical level the near neighbour spin ice model of ( [25]) is a "sixteen vertex" model of the ferroelectric type long studied by theoreticians ( [13]); the discovery of spin ice materials is giving a new experimental relevance to these models ( [53,54]). Modifications of the near neighbour model may be designed to include quantum mechanical effects ( [51]) or the effect of finite anisotropy ( [55]).…”

Quantum and thermal spin relaxation in the diluted spin iceDy2−xMxTi2O7Snyder1, Ueland2, Mizel3 et al. 2004Phys. Rev. B7311592View full textAdd to dashboardCite

“…Dilution studies of other geometrically frustrated magnets have lent considerable insight into the nature of the low temperature behavior. [21][22][23][24] For example, SrCr 8−x Ga 4+x O 19 (SCGO), a frustrated antiferromagnet with a layered kagomé structure 25,26 has been studied extensively as a function of the concentration of the Cr ions relative to nonmagnetic Ga. While not possessing the level of disorder traditionally associated with spin glasses, SCGO displays a spin glass transition at low temperatures ͑T f ϳ 5 KӶ⌰ Weiss ϳ 500 K͒, which is associated with the geometrical frustration inherent to the kagomé lattice.…”