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Bulgarian Journal of Physics
Print: 1310-0157 Online: 1314-2666
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RECOGNIZED BY THE EUROPEAN PHYSICAL SOCIETY 
Bulg. J. Phys. vol.30 no.1-2 (2003), pp. 52-59
Itinerant Vibronic Polarons: A Merrifield Approach. Low Energy Range Calculations
S.G. Tsintsarska1, A. Andreev1, M.D. Ivanovich2, M. Georgiev2, D.W. Brown3, K. Lindenberg3
1Central Laboratory for Photoprocesses, Bulgarian Academy of Sciences, 1113 Sofia, Bulgaria
2Institute of Solid State Physics, Bulgarian Academy of Sciences, 1784 Sofia, Bulgaria
3Department of Chemistry and Biochemistry, University of California San Diego, La Jolla, California 92093-0340, USA
go back1Central Laboratory for Photoprocesses, Bulgarian Academy of Sciences, 1113 Sofia, Bulgaria
2Institute of Solid State Physics, Bulgarian Academy of Sciences, 1784 Sofia, Bulgaria
3Department of Chemistry and Biochemistry, University of California San Diego, La Jolla, California 92093-0340, USA
Abstract. We extend Merrifield's Variational Ansatz in the variational band theory of polarons to cover a frame of two electronic bands mixed by an Einstein phonon. The Hamiltonian is composed of the local and hopping energy terms, the vibrational energy, and a band-mixing term linear in the electron-phonon coupling. The eigenstate is a linear combination of Merrifield states for either electron band. The variational equations are solved numerically, so as to obtain the energy vs. momentum relation in ground state. Our variational method generates either Jahn-Teller polarons if the electronic bands degenerate or pseudo-Jahn-Teller polarons if they nearly degenerate, both entities regarded as likely carriers in metal-oxygen manifolds of high-Tc superconducting cuprates and colossal magnetoresistance exhibiting manganates.