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arXiv · 1601.01169

Tuning the critical magnetic field of the triplon Bose-Einstein condensation in Ba$_{3-x}$Sr$_x$Cr$_2$O$_8$

Henrik Grundmann·Alsu Gazizulina·Fabian von Rohr·Laurens Peters·Tobias Förster·Andreas Schilling
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Abstract

The structure and magnetic interactions of the triplon Bose-Einstein condensation candidates Ba$_3$Cr$_2$O$_8$ and Sr$_3$Cr$_2$O$_8$ have been studied thoroughly in the literature, but little is known about a possible triplon condensation in the corresponding solid solution Ba$_{3-x}$Sr$_x$Cr$_2$O$_8$. We have prepared various members of this solid solution and systematically examined their magnetic properties in high magnetic fields up to 60 T and at low temperatures down to 340 mK, by means of pulsed field and cantilever magnetometry. From these experiments for $x\in\{3,2.9,2.8,2.7,2.6,2.5\}$, we find that the critical fields of Ba$_{3-x}$Sr$_x$Cr$_2$O$_8$ decrease monotonically as a function of the Sr content $x$. This change is in good agreement with the earlier reported variation of the magnetic interactions in these compounds.

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Henrik Grundmann, Alsu Gazizulina, Fabian von Rohr, Laurens Peters, Tobias Förster, Andreas Schilling. 2016-01-06. Tuning the critical magnetic field of the triplon Bose-Einstein condensation in Ba$_{3-x}$Sr$_x$Cr$_2$O$_8$. https://doi.org/10.1088/1367-2630/18/3/033001

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