Paper doi abstract bibtex

We show that coupling to vibrational degrees of freedom can drive a semimetal excitonic-insulator quantum phase transition in a one-dimensional two-band f-c-electron system at zero temperature. The insulating state typifies an excitonic condensate accompanied by a finite lattice distortion. Using the projector-based renormalization method we analyze the ground-state and spectral properties of the interacting electron-phonon model at half filling. In particular we calculate the momentum dependence of the excitonic order-parameter function and determine the finite critical interaction strength for the metal-insulator transition to appear. The electron spectral function reveals the strong hybridization of f- and c-electron states and the opening of a single-particle excitation gap. The phonon spectral function indicates that the phonon mode involved in the transition softens (hardens) in the adiabatic (nonadiabatic and extreme antiadiabatic) phonon frequency regime.

@article{phan_exciton_2013, title = {Exciton condensation due to electron-phonon interaction}, volume = {88}, url = {http://link.aps.org/doi/10.1103/PhysRevB.88.205123}, doi = {10.1103/PhysRevB.88.205123}, abstract = {We show that coupling to vibrational degrees of freedom can drive a semimetal excitonic-insulator quantum phase transition in a one-dimensional two-band f-c-electron system at zero temperature. The insulating state typifies an excitonic condensate accompanied by a finite lattice distortion. Using the projector-based renormalization method we analyze the ground-state and spectral properties of the interacting electron-phonon model at half filling. In particular we calculate the momentum dependence of the excitonic order-parameter function and determine the finite critical interaction strength for the metal-insulator transition to appear. The electron spectral function reveals the strong hybridization of f- and c-electron states and the opening of a single-particle excitation gap. The phonon spectral function indicates that the phonon mode involved in the transition softens (hardens) in the adiabatic (nonadiabatic and extreme antiadiabatic) phonon frequency regime.}, number = {20}, urldate = {2014-07-01}, journal = {Physical Review B}, author = {Phan, Van-Nham and Becker, Klaus W. and Fehske, Holger}, month = nov, year = {2013}, note = {269}, pages = {205123}, file = {APS Snapshot:/home/schlady/.zotero/zotero/za3jlr8i.default/zotero/storage/FUUU2GMH/PhysRevB.88.html:text/html;Phan et al_2013_Exciton condensation due to electron-phonon interaction.pdf:/home/schlady/.zotero/zotero/za3jlr8i.default/zotero/storage/JVK8N9M7/Phan et al_2013_Exciton condensation due to electron-phonon interaction.pdf:application/pdf} }

Downloads: 0