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Pseudogap State in High-$T_c$ Superconductors: an Infrared Study

A. V. Puchkov·D. N. Basov·T. Timusk
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Abstract

We report on a study of the electromagnetic response of three different families of high-T_c superconductors that in combination allowed us to cover the whole doping range from under- to overdoped. The discussion is focused on the ab-plane charge dynamics in the {\it pseudogap state} which is realized in underdoped materials below a characteristic temperature T^*; a temperature that can significantly exceed the superconducting transition temperature T_c. We explore the evolution of the pseudogap response by changing the doping level, by varying the temperature from the above to below T^*, or by introducing impurities in the underdoped compounds. We employ a memory-function analysis of the ab-plane optical data that allows us to observe the effect of the pseudogap most clearly. We compare the infrared data with other experimental results, including c-axis optical response, dc transport, and angular resolved photoemission.

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A. V. Puchkov, D. N. Basov, T. Timusk. 1996-11-12. Pseudogap State in High-$T_c$ Superconductors: an Infrared Study. https://arxiv.org/abs/cond-mat/9611083

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