Hague, J. P.
PDF (Not Set)
- Requires a PDF viewer such as GSview, Xpdf or Adobe Acrobat Reader
|DOI (Digital Object Identifier) Link:||http://doi.org/10.1088/0953-8984/15/17/309|
|Google Scholar:||Look up in Google Scholar|
I apply the newly developed dynamical cluster approximation (DCA) to the calculation of the electron and phonon dispersions in the two-dimensional Holstein model. In contrast to previous work, the DCA enables the effects of spatial fluctuations (non-local corrections) to be examined. Approximations neglecting and incorporating lowest-order vertex corrections are investigated. I calculate the phonon density of states, the renormalized phonon dispersion, the electron dispersion and electron spectral functions. I demonstrate how vertex corrections stabilize the solution, stopping a catastrophic softening of the (?, ?) phonon mode. A kink in the electron dispersion is found in the normal state along the (?, ?) symmetry direction in both the vertex- and non-vertex-corrected theories for low phonon frequencies, corresponding directly to the renormalized phonon frequency at the (?, 0) point. This kink is accompanied by a sudden drop in the quasi-particle lifetime. Vertex and non-local corrections enhance the effects at large bare phonon frequencies.
|Item Type:||Journal Article|
|Academic Unit/Department:||Science > Physical Sciences
|Interdisciplinary Research Centre:||Centre for Earth, Planetary, Space and Astronomical Research (CEPSAR)
Biomedical Research Network (BRN)
|Depositing User:||James Hague|
|Date Deposited:||13 May 2009 14:51|
|Last Modified:||25 Feb 2016 07:23|
|Share this page:|
Download history for this item
These details should be considered as only a guide to the number of downloads performed manually. Algorithmic methods have been applied in an attempt to remove automated downloads from the displayed statistics but no guarantee can be made as to the accuracy of the figures.