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arXiv · 1111.2232

Insulator-to-metal transition and large thermoelectric effect in La$_{1-x}$Sr$_{x}$MnAsO

Yunlei Sun·Jinke Bao·Chunmu Feng·Zhu'an Xu·Guanghan Cao
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Abstract

We report the Sr substitution effect in an antiferromagnetic insulator LaMnAsO. The Sr doping limit is $x\sim$ 0.10 under the synthesis conditions, as revealed by x-ray diffractions indicate. Upon Sr doping, the room-temperature resistivity drops by five orders of magnitude down to $\sim$0.01 $Ω\cdot$cm, and the temperature dependence of resistivity shows essentially metallic behavior for $x\geq$0.08. Hall and Seebeck measurements confirm consistently that the insulator-to-metal transition is due to hole doping. Strikingly, the room-temperature Seebeck coefficient for the metallic samples is as high as $\sim240 μ$V/K, making the system as a possible candidate for thermoelectric applications.

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Yunlei Sun, Jinke Bao, Chunmu Feng, Zhu'an Xu, Guanghan Cao. 2011-11-09. Insulator-to-metal transition and large thermoelectric effect in La$_{1-x}$Sr$_{x}$MnAsO. https://doi.org/10.1209/0295-5075%2F98%2F17009

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