# Anomalous Positron Lifetime in Single Crystal of Weyl Semimetal CoSi

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## Abstract

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## 1. Introduction

## 2. Materials and Methods

## 3. Results and Discussion

## 4. Conclusions

## Author Contributions

## Funding

## Data Availability Statement

## Acknowledgments

## Conflicts of Interest

## Abbreviations

Ps | positronium |

PAL | positron annihilation lifetime |

PALS | positron annihilation lifetime spectroscopy |

## References

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**Figure 1.**Measured energy spectrum of an irradiated 50 $\mathsf{\mu}$m thick titanium foil. The blue points are data from the HPGe detector, and the green points are data from the LaBr${}_{3}$:Ce detector.

**Figure 2.**Time spectra of positron annihilation with the ${}^{48}$V source in titanium foil and their fittings for the CoSi, MnSi, and FeSi single crystals.

**Figure 3.**Time spectra of positron annihilation for the CoSi single crystal with the ${}^{22}$Na source and for the Si single crystal with the ${}^{48}$V source.

**Table 1.**Measured positron annihilation lifetimes (${\tau}_{\mathrm{exp}}$) in single crystals of Si, CoSi, MnSi, and FeSi (this work), compared with ${\tau}_{\mathrm{b}}$ in polycristalline samples (CoSi, MnSi, FeSi) and the Si single crystal with ${}^{22}$Na as a source of positrons.

Material | ${\mathit{\tau}}_{\mathbf{exp}}$, ps (in This Work) | ${\mathit{\tau}}_{\mathbf{b}}$, ps (According to Literature) |
---|---|---|

Si | 218(1) (with ${}^{48}$V) | 218(1) (single crystal) [43] |

CoSi | 168(1) (with ${}^{48}$V), 166(2) (with ${}^{22}$Na) | 115(2) (polycrystal) [28] |

FeSi | 114(1) (with ${}^{48}$V) | 130(3) (polycrystal) [31] |

MnSi | 111(1) (with ${}^{48}$V) | 119(3) (single crystal) [29] |

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## Share and Cite

**MDPI and ACS Style**

Salamatin, D.A.; Bokov, A.V.; Kozin, M.G.; Romashkina, I.L.; Salamatin, A.V.; Mikhin, M.V.; Petrova, A.E.; Sidorov, V.A.; Nikolaev, A.V.; Fisk, Z.;
et al. Anomalous Positron Lifetime in Single Crystal of Weyl Semimetal CoSi. *Crystals* **2023**, *13*, 509.
https://doi.org/10.3390/cryst13030509

**AMA Style**

Salamatin DA, Bokov AV, Kozin MG, Romashkina IL, Salamatin AV, Mikhin MV, Petrova AE, Sidorov VA, Nikolaev AV, Fisk Z,
et al. Anomalous Positron Lifetime in Single Crystal of Weyl Semimetal CoSi. *Crystals*. 2023; 13(3):509.
https://doi.org/10.3390/cryst13030509

**Chicago/Turabian Style**

Salamatin, D. A., A. V. Bokov, M. G. Kozin, I. L. Romashkina, A. V. Salamatin, M. V. Mikhin, A. E. Petrova, V. A. Sidorov, A. V. Nikolaev, Z. Fisk,
and et al. 2023. "Anomalous Positron Lifetime in Single Crystal of Weyl Semimetal CoSi" *Crystals* 13, no. 3: 509.
https://doi.org/10.3390/cryst13030509