Physics – Condensed Matter – Superconductivity
Scientific paper
1999-08-03
Physics
Condensed Matter
Superconductivity
Scientific paper
10.1103/PhysRevB.61.618
We have performed ellipsometric measurements of the far-infrared c-axis dielectric response of underdoped YBa$_{2}$Cu$_{3}$O$_{7-\delta}$ single crystals. Here we report a detailed analysis of the temperature-dependent renormalization of the oxygen bending phonon mode at 320 cm$^{-1}$ and the formation of the additional absorption peak around 400-500 cm$^{-1}$. For a strongly underdoped YBa$_{2}$Cu$_{3}$O$_{6.5}$ crystal with T$_{c}$=52 K we find that, in agreement with previous reports based on conventional reflection measurements, the gradual onset of both features occurs well above T$_{c}$ at T*$\sim $150 K. Contrary to some of these reports, however, our data establish that the phonon anomaly and the formation of the additional peak exhibit very pronounced and steep changes right at T$_{c}$. For a less underdoped YBa$_{2}$Cu$_{3}$O$_{6.75}$ crystal with T$_{c}$=80 K, the onset temperature of the phonon anomaly almost coincides with T$_{c}$. Also in contrast to some previous reports, we find for both crystals that a sizeable fraction of the spectral weight of the additional absorption peak cannot be accounted for by the spectral-weight loss of the phonon modes but instead arises from a redistribution of the electronic continuum. Our ellipsometric data are consistent with a model where the bilayer cuprate compounds are treated as a superlattice of intra- and inter-bilayer Josephson-junctions.
Bernhard Christian
Cardona Manuel
Golnik Andrzej
Huml{í}ček J.
Lin Tai-Chia
No associations
LandOfFree
The anomaly of the oxygen bond-bending mode at 320 cm$^{-1}$ and the additional absorption peak in the c-axis infrared conductivity of underdoped YBa$_{2}$Cu$_{3}$O$_{7-δ}$ single crystals revisited by ellipsometricmeasurements does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with The anomaly of the oxygen bond-bending mode at 320 cm$^{-1}$ and the additional absorption peak in the c-axis infrared conductivity of underdoped YBa$_{2}$Cu$_{3}$O$_{7-δ}$ single crystals revisited by ellipsometricmeasurements, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and The anomaly of the oxygen bond-bending mode at 320 cm$^{-1}$ and the additional absorption peak in the c-axis infrared conductivity of underdoped YBa$_{2}$Cu$_{3}$O$_{7-δ}$ single crystals revisited by ellipsometricmeasurements will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-669204