226 citations · 856 across the 20 of their papers we have counts for
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Magnon Dispersion and Anisotropies in SrCu(BO)
Y. F. Cheng, O. Cepas, P. W. Leung +1
We study the dispersion of the magnons (triplet states) in SrCu(BO) including all symmetry-allowed Dzyaloshinskii-Moriya interactions. We can reduce the complexity of t…
Instabilities and Insulator-Metal transitions in Half-Doped Manganites induced by Magnetic-Field and Doping
O. Cepas, H. R. Krishnamurthy, T. V. Ramakrishnan
We discuss the phase diagram of the two-orbital model of half-doped manganites by calculating self-consistently the Jahn-Teller (JT) distortion patterns, charge, orbital and magnet…
Degeneracy and Strong Fluctuation-Induced First-Order Phase Transition in the Dipolar Pyrochlore Antiferromagnet
O. Cepas, A. P. Young, B. S. Shastry
We show that a continuous set of degenerate critical soft modes strongly enhances the first-order character of a fluctuation-induced first-order transition in the pyrochlore dipola…
Doping and Field-Induced Insulator-Metal Transitions in Half-Doped Manganites
O. Cepas, H. R. Krishnamurthy, T. V. Ramakrishnan
We argue that many properties of the half-doped manganites may be understood in terms of a new two-(eg electron)-fluid description, which is energetically favorable at intermediate…
Modified Spin-Wave Theory for Nanomagnets : Application to the Keplerate Molecule Mo(72)Fe(30)
Olivier Cepas, Timothy Ziman
We adapt Takahashi's modified spin-wave theory to the context of nano-magnets, and apply it to the molecular compound based on the giant magnetic molecule Mo(72)Fe(30). This involv…