A systematic optical study of phonon properties in optimally doped Bi2Sr2CaCu2O8+d single crystals
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چکیده
A systematic optical study of infrared-active phonons is carried out for optimally doped Bi2Sr2CaCu2O8+d (Bi2212) single crystals with E-vector along c-axis as well as in the ab-plane at 295K. Strong phonon anisotropy has been observed in our ab-plane conductivity measurements. Ten infrared-active phonons have been observed along c-axis. Many of these c-axis infrared-active phonons have energies that are very close to the Raman-active A1g modes. The group theory analysis based on the tetragonal group (D4h) is inadequate to explain our experimental observations. r 2002 Elsevier Science B.V. All rights reserved. PACS: 74.25.Gz; 74.72.Hs; 74.25.Nf
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تاریخ انتشار 2002