µSR Investigation of Doped IrTe2

Murray Wilson

Jiaqiang Yan, David Mandrus, Timothy Munsie, Teresa Medina, Graeme Luke

Outline

• Motivation

• µSR Introduction

• Ir0.95Pt0.05Te2 TF µSR

• Fe0.33Ir0.83Te2 ZF µSR

• Conclusion

Ir Te

1/15

Motivation – IrTe2

P3 m1

Layered structure

High spin-orbit coupling

Structural transition

Matsumoto JLTP 1999

2/15

Motivation

Yang PRL 108 116402 (2012)

Yan arXiv:1309.4829v1

Feng Sci. Rep. 3 1153 2013

µSR Technique

3/15 J.E. Sonier Muon Spin Rotation/Relaxation/Resonance (µSR)

µSR Technique

4/15

µSR Technique

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Ir0.95Pt0.05Te2

𝐴(𝑡) = 𝐴𝑖cos(𝜔𝑖𝑡 + 𝜑𝑖)𝑒−12(𝜎𝑖𝑡)

22

𝑖=1

B = 300 G

TF µSR

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Pt-IrTe2

𝑛𝑠 =𝑚𝜎𝑆𝐶

0.043𝜇0𝑒2𝛾𝜇𝛷0 2

𝜎𝑆𝐶 = 𝜎2 − 𝜎𝑁

2

Superfluid Density

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Pt-IrTe2

𝑛𝑠 =𝑚

𝜇0𝜆02𝑒21 + 2 𝑑𝐸

𝑒𝐸/(𝑘𝐵𝑇)

(𝑒𝐸/(𝑘𝐵𝑇)+1)2

∞

Δ(𝑇)

𝐸

𝐸2 − ∆(𝑇)

∆ 𝑇 = ∆0tanh 1.837𝑇𝐶𝑇− 1

0.51

Superfluid Density

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Pt-IrTe2

Superfluid Density

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Pt-IrTe2

Ir0.95Pt0.05Te2

Present Work Ir0.95Pd0.05Te2 Ref. [1] (STS)

BCS weak coupling

∆0= 0.33 meV

𝑇𝐶 = 2.2K

2∆0𝑘𝐵𝑇𝐶= 3.5

∆0= 0.39 meV

𝑇𝐶 = 2.5K

2∆0𝑘𝐵𝑇𝐶= 3.6

2∆0𝑘𝐵𝑇𝐶= 3.5

[1] D.J. Yu et. al PRB 89, 100501(R) March 4 2014

BCS Comparison

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Fe0.33Ir0.83Te2 Single Crystal

ZF µSR

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Fe-IrTe2

ZF µSR

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Fe-IrTe2

𝐴 = 𝐴1𝐾𝑇(𝜎, 𝑡) + 𝐴2𝑒−𝜆1𝑡 + 𝐴3𝑒

−𝜆2𝑡

𝐾𝑇 𝜎, 𝑇 =1

3+2

31 − (𝜎𝑡)2 𝑒−(𝜎𝑡)

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ZF µSR

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Spin Glass TC ≈ 10K

Fe-IrTe2

ZF µSR

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Fe-IrTe2

J.-Q. Yan et al. arXiv:1309.4829v1 [cond-mat.supr-con] 19-09-2013

Fe-IrTe2 spin glass, TC ≈ 10K

Pt-IrTe2 weak coupling fully gapped BCS superconductor, TC = 2.24K

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Conclusions

Acknowledgments

Timothy Munsie Alannah Hallas Teresa Medina Dr. Graeme Luke

Lian Liu Benjamin Frandsen Dr. Yasutomo Uemura

Dr. Bassam Hitti Dr. Gerald Morris

Dr. Jiaqiang Yan Dr. David Mandrus