2006/02/02 by David W. Brown, Brown, D. W., Katja Lindenberg +3
Computer Science · Physics and Astronomy · #FOS: Physical sciences #Materials Science (cond-mat.mtrl-sci) #Quantum Information and Cryptography #Quantum and electron transport phenomena #Spectroscopy and Quantum Chemical Studies #Superconductivity (cond-mat.supr-con)
paper · pdf · doi:10.48550/arxiv.cond-mat/0602052
openalex publication_date 2006/02/02 · openalex created_date 2016/06/24 · openalex updated_date 2026/07/28
Merrifield's Variational Ansatz is extended so as to cover the case of two electronic bands mixed by an Einstein phonon. The Hamiltonian is composed of the local and kinetic (hopping) energies in the absence of vibrations, the vibrational energy, and a mixing band-off-diagonal part linear in the electron-phonon coupling, all expressed in second quantization terms. The variational eigenstate is a linear combination of Merrifield states for either electronic band. We derive equations for the phonon Fourier amplitudes and for the fractional contribution of either electronic band.