TY - JOUR
T1 - Amplitude solitons in incommensurate Peierls systems
T2 - Implications for TTF-TCNQ
AU - Krumhansl, J. A.
AU - Horovitz, B.
AU - Heeger, A. J.
N1 - Funding Information:
* Permanent address: Dept.of Physics, Cornell Umver-sity; supported by Army Research Office through Grant No. DAAG-29-C.0097.
Funding Information:
~ Permanent address: Supported by Army Research Office through Grant No. DAAG2977G0089.
PY - 1980/1/1
Y1 - 1980/1/1
N2 - Amplitude soliton excitations are described for both dimerized [i.e. commensurate with 2kf = ( π a)] and incommensurate charge-density- wave (CDW) ground states. For the dimerized case the soliton excitations can have charge + e, 0, - e with spin 0, ± 1 2, 0 depending on the occupancy of the localized gap state. For the incommensurate case only the neutral spin- 1 2 soliton exists. Utilizing the results of Takayama, Lin-Liu and Maki, we show that Es = ( 2 π)Δ where 2Δ is gap for electron-hole excitations (Δi = W exp ( -1 λ) for the incommensurate case and Δc = W exp (- 1 2λ) for the dimerized case where λ is the electron-phonon coupling constant and W is the bandwidth). We suggest that neutral soliton excitations may make significant contributions to the magnetic susceptibility of incommensurate CDW systems, and that this may be the origin of observed differences between the low-temperature magnetic and transport activation energies in TTF-TCNQ.
AB - Amplitude soliton excitations are described for both dimerized [i.e. commensurate with 2kf = ( π a)] and incommensurate charge-density- wave (CDW) ground states. For the dimerized case the soliton excitations can have charge + e, 0, - e with spin 0, ± 1 2, 0 depending on the occupancy of the localized gap state. For the incommensurate case only the neutral spin- 1 2 soliton exists. Utilizing the results of Takayama, Lin-Liu and Maki, we show that Es = ( 2 π)Δ where 2Δ is gap for electron-hole excitations (Δi = W exp ( -1 λ) for the incommensurate case and Δc = W exp (- 1 2λ) for the dimerized case where λ is the electron-phonon coupling constant and W is the bandwidth). We suggest that neutral soliton excitations may make significant contributions to the magnetic susceptibility of incommensurate CDW systems, and that this may be the origin of observed differences between the low-temperature magnetic and transport activation energies in TTF-TCNQ.
UR - http://www.scopus.com/inward/record.url?scp=0019025818&partnerID=8YFLogxK
U2 - 10.1016/0038-1098(80)91104-7
DO - 10.1016/0038-1098(80)91104-7
M3 - Article
AN - SCOPUS:0019025818
SN - 0038-1098
VL - 34
SP - 945
EP - 948
JO - Solid State Communications
JF - Solid State Communications
IS - 12
ER -