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Theory of Doped Excitonic Insulators

Leon Balents·Chandra M. Varma
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Abstract

The theory of doped excitonic insulators is reinvestigated in light of recent experiments on hexaborides. For the appropriate valley-degenerate X_3,X_3' band structure, ``intra-valley'' condensation is energetically favored. Ferromagnetism occurs upon doping due to the quenching of kinetic energy at the otherwise direct first-order excitonic insulator-metal transition. The phase diagram includes states of spatially inhomogeneous density and magnetization at low temperatures.

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Leon Balents, Chandra M. Varma. 1999-06-17. Theory of Doped Excitonic Insulators. https://arxiv.org/abs/cond-mat/9906259

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