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arXiv · 2410.01631

Disorder-resilient transition of Helical to Conical ground states in M$_{1/3}$NbS$_2$, M=Cr,Mn

Manaswini Sahoo·Pietro Bonfà·Amelia. E. Hall·Daniel. A. Mayoh·Laura T. Corredor·Anja U. B. Wolter·Bernd Büchner·Geetha Balakrishnan·Roberto De Renzi·Giuseppe Allodi
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Abstract

The discovery of chiral helical magnetism (CHM) in Cr$_{1/3}$NbS$_2$ and the stabilization of a chiral soliton lattice (CSL) has attracted considerable interest in view of their potential technological applications. However, there is an ongoing debate regarding whether the sister compound, Mn$_{1/3}$NbS$_2$, which shares the same crystal structure, exhibits similar nontrivial properties which rely on the stabilization of the lack of inversion symmetry at the magnetic ion. In this study, we conduct a comprehensive investigation of the magnetically ordered states of both compounds, using $^{53}$Cr, $^{55}$Mn and $^{93}$Nb nuclear magnetic resonance. Our results, supported by density functional calculations, detect in a high-quality single crystal of Cr$_{1/3}$NbS$_2$ all the signatures of the monoaxial CHM in a magnetic field, identifying it as a textbook NMR case. The detailed understanding of this prototypic behavior provides a reference for Mn$_{1/3}$NbS$_2$. Despite the much larger density of specific defects in this second single crystal, we confirm the presence of a CHM phase in the Mn compound, characterized by a very large critical field for the forced ferromagnetic phase ($\approx 5$ T for H$\parallel\hat c$).

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Manaswini Sahoo, Pietro Bonfà, Amelia. E. Hall, Daniel. A. Mayoh, Laura T. Corredor, Anja U. B. Wolter, Bernd Büchner, Geetha Balakrishnan, Roberto De Renzi, Giuseppe Allodi. 2024-10-02. Disorder-resilient transition of Helical to Conical ground states in M$_{1/3}$NbS$_2$, M=Cr,Mn. https://doi.org/10.1103/4jc9-b6dj

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