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arXiv · 1711.04890

Doping-induced quantum cross-over in Er$_2$Ti$_{2-x}$Sn$_x$O$_7$

Masae Shirai·Rafael S. Freitas·Jorge Lago·Steven T. Bramwell·Clemens Ritter·Ivica Živković
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Abstract

We present the results of the investigation of magnetic properties of the Er$_2$Ti$_{2-x}$Sn$_x$O$_7$ series. For small doping values the ordering temperature decreases linearly with $x$ while the moment configuration remains the same as in the $x = 0$ parent compound. Around $x = 1.7$ doping level we observe a change in the behavior, where the ordering temperature starts to increase and new magnetic Bragg peaks appear. For the first time we present evidence of a long-range order (LRO) in Er$_2$Sn$_2$O$_7$ ($x = 2.0$) below $T_N = 130$ mK. It is revealed that the moment configuration corresponds to a Palmer-Chalker type with a value of the magnetic moment significantly renormalized compared to $x = 0$. We discuss our results in the framework of a possible quantum phase transition occurring close to $x = 1.7$.

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Masae Shirai, Rafael S. Freitas, Jorge Lago, Steven T. Bramwell, Clemens Ritter, Ivica Živković. 2017-11-13. Doping-induced quantum cross-over in Er$_2$Ti$_{2-x}$Sn$_x$O$_7$. https://doi.org/10.1103/physrevb.96.180411

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