S. Freutel, J. D. Rameau, L. Rettig, I. Avigo, M. Ligges, Y. Yoshida, H. Eisaki, J. Schneeloch, R. D. Zhong, Z. J. Xu, G. D. Gu, U. Bovensiepen, and P. D. Johnson:
Phys. Rev. B 99 (8), 081116(R) (2019), pp.5;
The high-Tc superconducting cuprates are recognized as doped Mott insulators. Several studies indicate that as a function of doping and temperature, there is a crossover from this regime into a phase characterized as a marginal Fermi liquid. Several calculations of the doped Mott insulating phase indicate that the Fermi surface defines small pockets which at the higher doping levels switch to a full closed Fermi surface, characteristic of a more metallic system. Here we use femtosecond laser-based pump-probe techniques to investigate the structure of the Fermi surface in the underdoped region of Bi2Sr2CaCu2O8+d and compare it with that associated with the optimally doped material. We confirm the concept of a small pocket in the underdoped system consistent with theoretical predictions in this strongly correlated state.
The original publication is available by link DOI: 10.1103/PhysRevB.99.081116