Validity of Lee, Low and Pines Method in the Case of the Interaction of an Electron with a Single Lattice Oscillator

✍ Scribed by J. Devreese; R. Evrard

• Book ID: 105385688
• Publisher: John Wiley and Sons
• Year: 1963
• Tongue: English
• Weight: 530 KB
• Volume: 3
• Category: Article
• ISSN: 0370-1972
• DOI: 10.1002/pssb.19630031118

✦ Synopsis

Abstract

The LEE‐LOW‐PINES approximation (or LLP approximation) of polaron theory is applied to a model first studied by GROSS, in which the polarization field is supposed to have only one k‐component. The results are compared with the exact solutions obtained with GROSS' method. It is shown that, in the particular case of this model, the LLP approximation is not very satisfactory when the mean number of phonons is of the order of, or greater than, 1/2. Thus the relative smallness of the mean number of virtual phonons cannot provide an argument for the validity of the LLP method in the intermediate coupling region.