Physics – Condensed Matter
Scientific paper
1996-07-16
Physics
Condensed Matter
REVTeX, 8 pages, 7 figures
Scientific paper
10.1103/PhysRevB.56.3105
The Rice-Sneddon model for BaBiO$_3$ is a nice model Hamiltonian for considering the properties of polarons and bipolarons in a three-dimensional oxide crystal. We use exact diagonalization methods on finite samples to study the stability and properties of polarons and bipolarons. Because polarons, when they form, turn out to be very well-localized, we are able to converge accurately our calculations for two-electron bipolaron wavefunctions, accounting for the Coulomb interaction without approximation. Some of our results are compared with and interpreted by reference to the variational method of Landau and Pekar. We calculate both electronic and vibrational excitations of the small polaron solutions, finding a single vibrational state localized with the full symmetry of the polaron, which has its energy significantly increased. Both on-site (Hubbard) and long-range Coulomb repulsion are included in the bipolaron calculation, but due to the high degree of localization, the long-range part has only a small influence. For a reasonable on-site repulsion $U$ equal to 2 times the band width $W$, bipolaron formation is significantly suppressed; there is a large window of electron-phonon coupling where the polaron is stable but the bipolaron decays into two polarons.
Allen Philip B.
Kostur Vladimir N.
No associations
LandOfFree
Polaron and bipolaron formation in a cubic perovskite lattice does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Polaron and bipolaron formation in a cubic perovskite lattice, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Polaron and bipolaron formation in a cubic perovskite lattice will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-434636