First- and second-order phase transitions in the Holstein-Hubbard model
نویسندگان
چکیده
منابع مشابه
First - and Second Order Phase Transitions in the Holstein - Hubbard Model
– We investigate metal-insulator transitions in the half-filled Holstein-Hubbard model as a function of the on-site electron-electron interaction U and the electron-phonon coupling g. We use several different numerical methods to calculate the phase diagram, the results of which are in excellent agreement. When the electron-electron interaction U is dominant the transition is to a Mott-insulato...
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ژورنال
عنوان ژورنال: Europhysics Letters (EPL)
سال: 2004
ISSN: 0295-5075,1286-4854
DOI: 10.1209/epl/i2003-10228-6