Observation of pseudogap in MgB2.

  title={Observation of pseudogap in MgB2.},
  author={Swapnil Patil and V. R. R. Medicherla and Khadiza Ali and Ravi Shankar Singh and Pietro Manfrinetti and Federico Wrubl and Sudesh Kumar Dhar and Kalobaran Maiti},
  journal={Journal of physics. Condensed matter : an Institute of Physics journal},
  volume={29 46},
  • S. Patil, V. Medicherla, +5 authors K. Maiti
  • Published 1 March 2017
  • Physics, Medicine
  • Journal of physics. Condensed matter : an Institute of Physics journal
We investigate the electronic structure of a specially prepared highly dense conventional high temperature superconductor, MgB2, employing high resolution photoemission spectroscopy. The spectral evolution close to the Fermi energy is commensurate to BCS descriptions as expected. However, the spectra in the wider energy range reveal the emergence of a pseudogap much above the superconducting transition temperature indicating an apparent departure from the BCS scenario. The energy scale of the… 
Pseudogap Isotope Effect as a Probe of Bipolaron Mechanism in High Temperature Superconductors
It is shown that the results obtained, in particular, the possibility of negative values of the isotope coefficient, are consistent with the experiment and new experiments on the influence of the magnetic field on the isotopes coefficient are proposed.
Dimensionality, nematicity and superconductivity in Fe-based systems
Abstract Study of Fe based compounds have drawn much attention due to the discovery of superconductivity as well as many other exotic electronic properties. Here, we review some of our works in these
Mathematical foundations of the translation-invariant bipolaron theory of superconductivity
The monograph presents the theory of translation-invariant polarons and bipolarons based on the theory of squeezed vacuum wave functions. It is shown that the Tulub ansatz, which establishes a


Role of the E2g phonon in the superconductivity of MgB2: a Raman scattering study
Abstract Temperature-dependent Raman scattering studies in polycrystalline MgB2 (10 K ) reveal that the E2g phonon does not experience any self-energy renormalization effect across the
Electron-phonon coupling induced pseudogap and the superconducting transition in Ba0.67K0.33BiO3
We study the single particle density of states (DOS) across the superconducting transition (Tc = 31 K) in single-crystal Ba0.67K0.33BiO3 using ultrahigh resolution angle-integrated photoemission
The pseudogap in high-temperature superconductors: an experimental survey
We present an experimental review of the nature of the pseudogap in the cuprate superconductors. Evidence from various experimental techniques points to a common phenomenology. The pseudogap is seen
Definitive experimental evidence for two-band superconductivity in MgB2.
The results show that superconducting gaps with values of 5.5 and 2.2 meV open on the sigma band and the pi band but both the gaps close at the bulk transition temperature, providing a definitive experimental evidence for the two-band superconductivity with strong interband pairing interaction in MgB2.
Complex spectral evolution in a BCS superconductor, ZrB12
The spectral simulation of the dip and spectral lineshape based on a phenomenological self energy suggests finite electron pair lifetime and a pseudogap above the superconducting transition temperature.
Momentum dependence of the superconducting gap and in-gap states in MgB2 multi-band superconductor
We use tunable laser based Angle Resolved Photoemission Spectroscopy to study the electronic structure of the multi-band superconductor, MgB2. These results form the base line for detailed studies of
High-resolution photoemission study of MgB2.
The present results strongly suggest that MgB2 is categorized into a phonon-mediated BCS superconductor in the weak-coupling regime.
Evolution of a band insulating phase from a correlated metallic phase
We investigate the evolution of the electronic structure in SrRu 1-x Ti x O 3 as a function of x using high resolution photoemission spectroscopy, where SrRuO 3 is a weakly correlated metal and SrTiO
Pseudogap in a thin film of a conventional superconductor.
It is shown that a pseudogap exists in a conventional superconductor, ultrathin titanium nitride films, over a wide range of temperatures above T(c), and is induced by superconducting fluctuations and favoured by two-dimensionality and by the proximity to the transition to the insulating state.
Small and large pseudogaps in high-Tc superconductors observed by ultrahigh-resolution photoemission spectroscopy
Abstract Two different (small and large) pseudogaps have been observed by ultrahigh-resolution photoemission spectroscopy in optimally doped Bi 2 Sr 2 CaCu 2 O 8 and La 1.85 Sr 0.15 CuO 4 . The small