Collective excitations in the charge-ordered phase of α-(BEDT-TTF)2I3
T Ivek1, B Korin-Hamzić, O Milat
1Institut za fiziku, P.O. Box 304, HR-10001 Zagreb, Croatia. tivek@ifs.hr
Abstract:
The charge response of a charge-ordered state in the organic conductor α-(BEDT-TTF)2I3 is characterized by dc resistivity, dielectric and optical spectroscopy in different crystallographic directions within the two-dimensional conduction layer. Two dielectric modes are detected. The large mode is related to the phasonlike excitation of the 2k(F) bond-charge density wave which forms in the ab plane. The small dielectric mode is associated with the motion of domain-wall pairs along the a and b axes between two types of domains which are created due to inversion symmetry breaking.
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