New type of Cooper pairing in systems with strong electron-phonon interaction

Journal Article · Sun May 01 04:00:00 EDT 1988 · Phys. Rev. B: Condens. Matter; (United States)

DOI:https://doi.org/10.1103/PhysRevB.37.7419· OSTI ID:5183265

Hang, Z

We have investigated the ground-state properties of a model system with a strong electron-phonon interaction. It is found that as long as the renormalized intersite electron correlation is attractive, a new type of Cooper pairing will occur whether the renormalized on-site electron correlation is repulsive or attractive. Furthermore, we have shown that a new phonon coherent state, named a two-phonon coherent state, must be introduced to serve as the ground state of the phonon subsystem, so that the ground-state energy of the interacting system can be made a stable minimum and an appropriate condensation energy of the superconducting ground state may be obtained. We have performed numerical calculations for the n = 1 case.

• Research Organization: Center of Theoretical Physics, Chinese Center of Advanced Science and Technology (World Laboratory), Beijing, The People's Republic of China People's Republic of China
• OSTI ID: 5183265
• Journal Information: Phys. Rev. B: Condens. Matter; (United States), Journal Name: Phys. Rev. B: Condens. Matter; (United States) Vol. 37:13; ISSN PRBMD
• Country of Publication: United States
• Language: English

Related Subjects

656100* -- Condensed Matter Physics-- Superconductivity
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
COOPER PAIRS
CORRELATIONS
ELECTRIC CONDUCTIVITY
ELECTRICAL PROPERTIES
ELECTRON CORRELATION
ELECTRON GAS
ELECTRON-PHONON COUPLING
ENERGY LEVELS
FLUIDS
GASES
GROUND STATES
PHYSICAL PROPERTIES
SUPERCONDUCTIVITY