Evolution of helimagnetic correlations when approaching the quantum critical point of Mn1-xFexSi

C. Pappas, A.O. Leonov, L.J. Bannenberg, P Fouquet, T. Wolf, F Weber

Research output: Contribution to journalArticleScientificpeer-review

1 Citation (Scopus)
4 Downloads (Pure)


We present a comprehensive investigation of the evolution of helimagnetic correlations in Mn1−xFexSi with increasing doping. By combining polarized neutron scattering and high resolution neutron spin echo spectroscopy we investigate three samples with x = 0.09, 0.11, and 0.14, i.e., with compositions on both sides of the concentration x∗∼0.11 where the helimagnetic Bragg peaks disappear and between x∗ and the quantum critical concentration xC∼0.17, where TC vanishes. We find that the abrupt disappearance of the long range helical periodicity at x∗ does not affect the precursor fluctuating correlations. These build up with decreasing temperature in a similar way as for the parent compound MnSi. Also the dynamics bears strong similarities to MnSi. The analysis of our results indicates that frustration, possibly due to achiral Ruderman-Kittel-Kasuya-Yosida (RKKY) interactions, increases with increasing Fe doping. We argue that this effect explains both the expansion of the precursor phase with increasing x and the abrupt disappearance of long range helimagnetic periodicity at x∗.
Original languageEnglish
Article number013019
Pages (from-to)1-7
JournalPhysical Review Research
Issue number1
Publication statusPublished - 8 Jan 2021


Dive into the research topics of 'Evolution of helimagnetic correlations when approaching the quantum critical point of Mn1-xFexSi'. Together they form a unique fingerprint.

Cite this