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Systematic Low-Energy Effective Field Theory for Electron-Doped Antiferromagnets

C. Brügger·C. P. Hofmann·F. Kämpfer·M. Moser·M. Pepe·U. -J. Wiese
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Abstract

In contrast to hole-doped systems which have hole pockets centered at $(\pm \fracπ{2a},\pm \fracπ{2a})$, in lightly electron-doped antiferromagnets the charged quasiparticles reside in momentum space pockets centered at $(\fracπ{a},0)$ or $(0,\fracπ{a})$. This has important consequences for the corresponding low-energy effective field theory of magnons and electrons which is constructed in this paper. In particular, in contrast to the hole-doped case, the magnon-mediated forces between two electrons depend on the total momentum $\vec P$ of the pair. For $\vec P = 0$ the one-magnon exchange potential between two electrons at distance $r$ is proportional to $1/r^4$, while in the hole case it has a $1/r^2$ dependence. The effective theory predicts that spiral phases are absent in electron-doped antiferromagnets.

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C. Brügger, C. P. Hofmann, F. Kämpfer, M. Moser, M. Pepe, U. -J. Wiese. 2006-12-14. Systematic Low-Energy Effective Field Theory for Electron-Doped Antiferromagnets. https://doi.org/10.1103/physrevb.75.214405

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