Charge density waves due to electron-phonon interaction in low-dimensional systems
Friday December 07, 2007
Refreshments are served at 3:00 p.m. in Physics room 242.
Prof. Sudhakar Yarlagadda
Saha Institute of Nuclear Physics
We derive analytically the effective Hamiltonian for interacting polarons in the Holstein model in d-dimensions. We map the effective Hamiltonian in 1d onto a next-to-nearest-neighbor interaction anisotropic Heisenberg model and study the Luttinger liquid to charge density wave (CDW) transition [1]. We also derive the Peierls instability condition and predict the phase diagram away from half-filling [2]. We extend our treatment to include cooperative Jahn-Teller effect in one-dimensional manganites and predict a novel conducting commensurate CDW.
1) Phys. Rev. B, vol. 71, 235118 (2005).
2) Phys. Rev. B, vol. 75, 035124 (2007)
