Amplitude breathers in conjugated polymers

Journal Article · Sat Jul 15 04:00:00 EDT 1989 · Phys. Rev. B: Condens. Matter; (United States)

DOI:https://doi.org/10.1103/PhysRevB.40.1839· OSTI ID:5972719

Phillpot, S R; Bishop, A R; Horovitz, B

Nonlinear adiabatic dynamics of electron-phonon models of /ital trans/-(CH)/sub /ital x//, /ital cis/-(CH)/sub /ital x//, and (/ital AB/)/sub /ital x//-type polymers are studied. Using both analytic low-amplitude expansion and numerical simulations, we find the existence of charge-neutral breathers---spatially localized, time-periodic nonlinear excitations. Simulations also show that a photoexcited electron-hole pair generates a breather in addition to a soliton-antisoliton pair. Semiclassical quantization shows that the /ital n/th breather is a bound state of /ital n/ amplitude phonons. A semiclassical formalism of optical absorption is applied to /ital trans/-(CH)/sub /ital x//; the ground-state result accounts for a pronounced intragap absorption tail, while breathers can account for the observed photoinduced absorption at 1.35 eV.

• Research Organization: Materials Science Division, Argonne National Laboratory, Argonne, Illinois 60439(US); Theoretical Division and Center for Nonlinear Studies, Los Alamos National Laboratory, Los Alamos, New Mexico 87545; Department of Physics, Ben-Gurion University, P.O. Box 653, 84105 Beer-Sheva, Israel
• DOE Contract Number: W-31109-ENG-38
• OSTI ID: 5972719
• Journal Information: Phys. Rev. B: Condens. Matter; (United States), Journal Name: Phys. Rev. B: Condens. Matter; (United States) Vol. 40:3; ISSN PRBMD
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360603* -- Materials-- Properties
BOND ANGLE
BOUND STATE
CHEMICAL REACTIONS
DIMERIZATION
ELECTRON-HOLE COUPLING
ELECTRON-PHONON COUPLING
ELECTRONIC STRUCTURE
ENERGY GAP
ENERGY LEVELS
EXCITED STATES
HAMILTONIANS
HYDROCARBONS
MATHEMATICAL OPERATORS
OPTICAL PROPERTIES
ORGANIC COMPOUNDS
ORIENTATION
PHYSICAL PROPERTIES
POLYACETYLENES
POLYENES
POLYMERIZATION
POLYMERS
QUANTUM OPERATORS
QUASI PARTICLES
ROTATIONAL STATES
SOLITONS
TIME DEPENDENCE