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arXiv · cond-mat/9611194

Evolution of the Fermi surface with carrier concentration in Bi_2Sr_2CaCu_2O_{8+δ}

H. Ding·M. R. Norman·T. Yokoya·T. Takeuchi·M. Randeria·J. C. Campuzano·T. Takahashi·T. Mochiku·K. Kadowaki
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Abstract

We show, by use of angle-resolved photoemission spectroscopy, that underdoped Bi_2Sr_2CaCu_2O_{8+δ} appears to have a large Fermi surface centered at (π,π), even for samples with a T_c as low as 15 K. No clear evidence of a Fermi surface pocket around (π/2,π/2) has been found. These conclusions are based on a determination of the minimum gap locus in the pseudogap regime T_c < T < T^*, which is found to coincide with the locus of gapless excitations in momentum space (Fermi surface) determined above T^*. These results suggest that the pseudogap is more likely of precursor pairing rather than magnetic origin.

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H. Ding, M. R. Norman, T. Yokoya, T. Takeuchi, M. Randeria, J. C. Campuzano, T. Takahashi, T. Mochiku, K. Kadowaki. 1996-11-25. Evolution of the Fermi surface with carrier concentration in Bi_2Sr_2CaCu_2O_{8+δ}. https://doi.org/10.1103/physrevlett.78.2628

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