Antiferromagnetism in the 2D Hubbard Model – Phase Transition and Local Quantities
نویسندگان
چکیده
We present a first study of the antiferromagnetic state in the 2D U–t–t′ model at finite temperatures by the composite operator method, providing simultaneously a fully self–consistent treatment of the paramagnetic and the AF phase. Near half filling the critical value of the Coulomb repulsion as a function of t′ and the temperature dependence of the magnetization and internal energy have been studied.
منابع مشابه
ابررسانای d- موجی، پادفرومغناطیس و مایع اسپینی در ابررساناهای آلی شبه دوبعدی
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