Conical spin arrangement and spin reorientation process in Er2-xHoxFe14B observed with Mössbauer spectroscopy

• Spin reorientation process has been studied in a new series of Er2-xHoxFe14B.
• Unique method of simultaneous spectra analysis is presented.
• Computer simulation of spin reorientation process is performed.
• Temperature dependence of tilt angle is presented.
• Spin arrangement diagram is constructed.

The series of Er2-xHoxFe14B (x = 0.5, 1.0, 1.5, 2.0) intermetallic compounds was studied in order to investigate different types of spin arrangements expected in this series. The variety of processes connected with spin reorientation, especially transition through conical spin arrangements was of special interest. The compounds have been measured with 57Fe Mössbauer spectroscopy over the temperature range 5.2–320 K. Each compound was studied with precise Mössbauer scanning in the vicinity of the transition. A special fitting procedure of Mössbauer spectra, enabling to analyze up to ten spectra simultaneously, was developed to determine the arrangement of spins. The path of spin rotation was proposed. The results were verified and compared by applying computer simulations based on the Yamada-Kato model. The spin arrangement diagram was constructed. Obtained results are convincing enough to conclude that Mössbauer spectroscopy can be very helpful in studies of tilt angle in conical spin arrangements in the studied type compounds.