کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
1819921 | 1525771 | 2007 | 5 صفحه PDF | دانلود رایگان |
عنوان انگلیسی مقاله ISI
Pairing symmetries in a Hubbard model on an anisotropic triangular lattice
دانلود مقاله + سفارش ترجمه
دانلود مقاله ISI انگلیسی
رایگان برای ایرانیان
کلمات کلیدی
موضوعات مرتبط
مهندسی و علوم پایه
فیزیک و نجوم
فیزیک ماده چگال
پیش نمایش صفحه اول مقاله
چکیده انگلیسی
To consider the paring symmetry formed in organic compounds κ-(BEDT-TTF)2X, we study the half-filled-band Hubbard model on an anisotropic triangular lattice (t in two bond directions and tâ² in the other), using an optimization VMC method. As trial states, we adopt a coexisting state of an antiferromagnetic (AF) order and the dx2-y2-wave RVB gap, in addition to the d + id- and d + d-wave gap states. In these states, we take account of the effect of band (or Fermi surface) renormalization. Magnetic Mott transitions occur, and a regime of robust superconductivity could not be found, in contrast with our previous study. In the insulating regime, the coexisting state in which an AF order prevails is always the lowest-energy state up to remarkably large tâ²/t (â²1.3), whereas a dxy-wave RVB state becomes predominant when tâ²/t exceeds this value. In the insulating regime, the effective Fermi surface, determined by the renormalized value tËâ²/t, is markedly renormalized into different directions according to tâ²/t; for tâ²/t â²Â 1.3, it approaches that of the square lattice (tËâ²/t=0), whereas for tâ²/t â³Â 1.3, it becomes almost one-dimensional (tËâ²/tâ«1).
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Physica C: Superconductivity and its Applications - Volumes 463â465, 1 October 2007, Pages 152-156
Journal: Physica C: Superconductivity and its Applications - Volumes 463â465, 1 October 2007, Pages 152-156
نویسندگان
Tsutomu Watanabe, Hisatoshi Yokoyama, Yukio Tanaka, Jun-ichiro Inoue,