Browsing by Author "Ebeling, W."
Now showing 1 - 3 of 3
Results Per Page
Sort Options
- Electron pairing in one-dimensional anharmonic crystal latticesPublication . Velarde, M. G.; Brizhik, L.; Chetverikov, A. P.; Cruzeiro, Leonor; Ebeling, W.; Röpke, G.We show that when anharmonicity is added to the electron–phonon interaction it facilitates electron pairing in a localized state. Such localized state appears as singlet state of two electrons bound with the traveling local lattice soliton distortion, which survives when Coulomb repulsion is included.
- On the possibility of electric transport mediated by long living intrinsic localized solectron modesPublication . Cantu Ros, O. G.; Cruzeiro, Leonor; Velarde, M. G.; Ebeling, W.We consider a polaron Hamiltonian in which not only the lattice and the electron-lattice interactions, but also the electron hopping term is affected by anharmonicity. We find that the one-electron ground states of this system are localized in a wide range of the parameter space. Furthermore, low energy excited states, generated either by additional momenta in the lattice sites or by appropriate initial electron conditions, lead to states constituted by a localized electron density and an associated lattice distortion, which move together through the system, at subsonic or supersonic velocities. Thus we investigate here the localized states above the ground state which correspond to moving electrons. We show that besides the stationary localized electron states (proper polaron states) there exist moving localized solectron states which can be easily excited. The evolution of these localized states suggests their potential as new carriers for fast electric charge transport.
- Quartic lattice interactions, soliton-like excitations, and electron pairing in one-dimensional anharmonic crystalsPublication . Velarde, M. G.; Brizhik, L.; Chetverikov, A. P.; Cruzeiro, Leonor; Ebeling, W.; Röpke, G.In this study, it is shown that two added, excess electrons with opposite spins in one-dimensional crystal lattices with quartic anharmonicity may form a bisolectron, which is a localized bound state of the paired electrons to a soliton-like lattice deformation. It is also shown that when the Coulomb repulsion is included, the wave function of the bisolectron has two maxima, and such a state is stable in lattices with strong enough electron (phonon/soliton)–lattice coupling. Furthermore, the energy of the bisolectron is shown to be lower than the energy of the state with two separate, independent electrons, as even with account of the Coulomb repulsion the bisolectron binding energy is positive.