ar X iv : c on d - m at / 9 51 10 29 v 2 1 3 N ov 1 99 5 Spin gap in CaV 4 O 9 : a large S approach Marc

نویسنده

  • Frédéric Mila
چکیده

We study the stability of the 4-site plaquette order in a model recently introduced by Katoh and Imada to explain the spin gap observed in CaV4O9. We show that all relevant types of order (4-site plaquette, dimerized, Néel) can be described within the framework of Schwinger boson mean field theory, and we make predictions regarding their relative stability. The results are compared to exact diagonalization of finite clusters.

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تاریخ انتشار 1995