Physikalisches Kolloquium

Darren Peets

TU Dresden

Hydrothermal Growth and Magnetic Phase Diagrams of Antlerite, Cu₃SO₄(OH)₄

Abstract:

The natural mineral antlerite contains three-leg triangular-lattice ladders of Cu²⁺, which has S=½ quantum spins.  This unusual magnetic sublattice has not been studied in detail, but we previously showed that antlerite hosts four magnetically ordered states at zero field alone.  However, our previous work was limited by sample size — our largest single crystals were only ~0.8×0.5×0.3 mm³.  We have now grown crystals several mm³ in size hydrothermally, which has enabled a detailed magnetic phase diagram study, and I will show the phase diagrams obtained from magnetization and specific heat for fields applied along the a, b, and c axes.  Along the a axis alone, we find at least 9 distinct magnetically ordered phases.  We anticipate that antlerite will be a rich source of interesting physics, and will be readily tuned by other means such as strain and pressure.