Crystal growth and doping control of HgBa2CuO4+δ, the model compound for high-T superconductors

A. Legros (1, 2) , B. Loret (1, 3, 2) , A. Forget (1) , P. Bonnaillie (4) , G. Collin (5) , Pierre Thuéry (6) , A. Sacuto (3) , D. Colson (1)

1 LNO - Laboratoire Nano-Magnétisme et Oxydes
2 UdeS - Département de physique [Sherbrooke]
3 MPQ (UMR_7162) - Laboratoire Matériaux et Phénomènes Quantiques
4 SRMP - Service de recherches de métallurgie physique
5 LPS - Laboratoire de Physique des Solides
6 LCMCE - Laboratoire de Chimie Moléculaire et de Catalyse pour l'Energie (ex LCCEF)

A self-flux method to grow very high quality single crystals of the superconducting HgBa2CuO4+δ mercury cuprates is reported. The single crystals are platelet-shaped, with surfaces of high optical quality and good crystallographic properties. Annealing enables optimization of Tc up to Tc max = 94 K. With adequate treatment, the doping level of the crystalline samples can be finely controlled in a wide under-and over-doped range. Preliminary structural characterization from single crystal X-ray diffraction data is given for different doping levels. The signature of under-and over-doping for both pure and gold-substituted crystals has been identified from micro-Raman spectroscopy measurements.

Keywords: X-ray diffraction; superconductors; crystal growth; magnetic properties; Raman spectroscopy

Domains: Cristallography

A. Legros, B. Loret, A. Forget, P. Bonnaillie, G. Collin, et al.. Crystal growth and doping control of HgBa2CuO4+δ, the model compound for high-T superconductors. Materials Research Bulletin, 2019, 118, pp.110479. ⟨10.1016/j.materresbull.2019.05.004⟩. ⟨cea-02145955⟩