This group interests are focused in the properties of unconventional superconductors, specially in the superconducting and pseudogap phase properties of the high temperature cuprates superconductors.

Cuprates can be considered as doped antiferromagnetic Mott insulators, and therefore strongly correlated systems. Doping can be via electrons or holes. To understand these materials one have to focus on the electronic properties of its CuO2 planes, where the Cu atoms are arranged in a square lattice. The t-J and Hubbard models on a square lattice are the simplest models that can describe the physics of these planes.
Current research areas
  • Charge instabilities in the t-J model (Figure 1). Comparison with recent experiments.
  • Physical properties of the pseudogap phase. Theoretical analysis from angle resolved photoemission spectroscopy (ARPES), Raman, Kerr effect, and optical conductivity experiments (Figure 2).
  • Isotopic effect of the superconducting critical temperature.
  • High energy contributions in the Raman spectra, and its possible interpretation in terms of two magnon scattering.
  • Retarded and unretarded interactions, and their contribution to superconductivity.
  • Valence bond solid phases in spin systems.
diagfase
Figure 1: Temperature-doping phase diagram showing the instabilities of the t-t'-J model in the square lattice [from To be published in New Journal of Physics (2014)].
arcos
Figure 2: Doping evolution of Fermi arcs [from J. Phys.: Condens. Matter 26 485701 (2014)].
Group members
  • Dr. Andrés Greco, Inv. Independiente de CONICET.
  • Dr. Matías Bejas, Inv. Asistente de CONICET.
  • Lic. Agustín Ferreyra, Becario Doctoral de CONICET.
  • Dra. Adriana Foussats, Inv. Independiente de CONICET (Retired).
Current international cooperations
  • Prof. Dr. Roland Zeyher, Max-planck Institut, Stuttgart, Alemania.
  • Prof. Dr. Alejandro Muramatsu, Universidad de Stuttgart, Alemania.
  • Dr. Hiroyuki Yamase, NIMS, Tsukuba, Japón.
Resultados recientes (últimos cinco años, 2010-2014)
  • To be published in New Journal of Physics (2014). Strong particle-hole asymmetry of charge instabilities in doped Mott insulators. Matías Bejas, Andrés Greco, and Hiroyuki Yamase.
  • J. Phys.: Condens. Matter 26 485701 (2014). Pseudogap in cuprates driven by d-wave flux-phase order proximity effects: A theoretical analysis from Raman and ARPES experiments. Andrés Greco and Matías Bejas.
  • Phys. Rev. B 89, 024516 (2014). Self-energy effects in cuprates and the dome-shaped behavior of the superconducting critical temperature. Guillermo Buzon, Adriana Foussats, Matías Bejas, and Andrés Greco.
  • Phys. Rev. B 87, 224511 (2013). Self-energy effects in electronic Raman spectra of doped cuprates due to magnetic fluctuations. Roland Zeyher and Andrés Greco.
  • Phys. Rev. B 86, 224509 (2012). Possible charge instabilities in the two-dimensional doped Mott insulators. Matías Bejas, Andrés Greco, and Hiroyuki Yamase.
  • Phys. Rev. B 83, 212503 (2011). Short-ranged and short-lived charge-density-wave order and pseudogap features in underdoped cuprate superconductors. Andrés Greco and Matías Bejas.
  • Europhysics Letters 93 67002 (2011). Fermi arcs and isotope effect of the magnetic penetration depth in underdoped cuprates. Roland Zeyher and Andrés Greco.
  • Phys. Rev. B 83, 014514 (2011). Doping and temperature dependence of the pseudogap and Fermi arcs in cuprates from d-CDW with short-range fluctuations in the context of the t- J model. Matías Bejas, Guillermo Buzon, Andrés Greco, and Adriana Foussats.
  • Nuclear Physics B, 842, Issue 2, Pages 225-247 (2011). Path integrals for dimerized quantum spin systems. Adriana Foussats, Andrés Greco, Alejandro Muramatsu.
  • Phys. Rev. Lett. 105, 206402 (2010). Bandwidth Tuning Triggers Interplay of Charge Order and Superconductivity in Two-Dimensional Organic Materials. S. Kaiser, M. Dressel, Y. Sun, A. Greco, J. A. Schlueter, G. L. Gard, and N. Drichko.
  • Phys. Rev. B 82, 054526 (2010). Two distinct quasiparticle inelastic scattering rates in the t-J model and their relevance for high-Tc cuprate superconductors. Guillermo Buzon and Andrés Greco.