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arXiv · 1812.01489

Crystal Growth and Doping Control of HgBa2CuO4+{\delta}, the Model Compound for High-Tc Superconductors

Anaëlle Legros·Bastien Loret·Anne Forget·Patrick Bonnaillie·Gaston Collin·Pierre Thuéry·Alain Sacuto·Dorothée Colson
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Abstract

A new method to grow very high quality single crystals of the superconducting HgBa2CuO4+{\delta} 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 Tcmax = 94 K. With adequate treatment, the doping level of the crystalline samples can be finely controlled in a wide under- and over-doped range. Complete structural characterization from single crystal X-ray diffraction data is given for the first time for different doping levels. The role of added gold on the doping is also investigated. The signature of under- and over-doping for both pure and gold-substituted crystals has been identified from micro-Raman spectroscopy measurements.

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Anaëlle Legros, Bastien Loret, Anne Forget, Patrick Bonnaillie, Gaston Collin, Pierre Thuéry, Alain Sacuto, Dorothée Colson. 2018-12-04. Crystal Growth and Doping Control of HgBa2CuO4+{\delta}, the Model Compound for High-Tc Superconductors. https://arxiv.org/abs/1812.01489

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