Fig. 5

Correlation of DMI with \({\boldsymbol{m}}_{\mathbf{o}}^ \bot /{\boldsymbol{m}}_{\mathbf{o}}^\parallel\) and m _D , and theoretical calculations based on the tight binding model and DFT. a Normalized \({\boldsymbol{m}}_{\mathrm{o}}^ \bot /{\boldsymbol{m}}_{\mathbf{o}}^\parallel\) and m_D vs D. Values of \({\boldsymbol{m}}_{\mathrm{o}}^ \bot /{\boldsymbol{m}}_{\mathbf{o}}^\parallel\) and m_D for all temperatures are normalized by the values measured at 300 K. b Calculated \({\boldsymbol{m}}_{\mathrm{o}}^ \bot\), \({\boldsymbol{m}}_{\mathbf{o}}^\parallel\) and E_DMI values based on the tight-binding model as a function of temperature. Inset shows \(f_{{\mathrm{SD}}}^ \bot\)/\(f_{{\mathrm{SD}}}^\parallel\) as a function of temperature. c Physical parameters such as total D (D^tot), \({\boldsymbol{m}}_{\mathrm{o}}^ \bot /{\boldsymbol{m}}_{\mathbf{o}}^\parallel\), m_D and m_s obtained by DFT calculation. Strength and sign of D^tot are calculated around their magnetic ground state using the combination of the relativistic effect spin–orbit coupling with the spin spirals. A positive sign of D^tot indicates a left-rotational sense or left chirality