spin reorientation in the er 2-x fe 14+2x si 3 single-crystal studied by mössbauer spectroscopy j....

Spin reorientation in the Er2-xFe14+2xSi3

single-crystal studied by Mössbauer spectroscopy

J. Żukrowski 1, A. Błachowski 2, K. Ruebenbauer 2, J. Przewoźnik 1,D. Sitko 3, N.-T.H. Kim-Ngan 3, Z. Tarnawski 1, A.V. Andreev 4

1 Solid State Physics Department, Faculty of Physics and Applied Computer Science,

AGH University of Science and Technology, Kraków, Poland

2 Mössbauer Spectroscopy Division, Institute of Physics, Pedagogical University, Kraków, Poland

3 Surface Physics Division, Institute of Physics, Pedagogical University, Kraków, Poland

4 Institute of Physics, Academy of Sciences, Prague, Czech Republic

Bulk magnetic moment versus temperature in the moderate external field 0.1 T aligned along the c-axis

Er2-xFe14+2xSi3 single-crystal

Magnetic susceptibility versus temperature for various AC frequencies in the null external field and for the moderate external field 0.1 T applied along the c-axis.

The AC field was applied along the c-axis.

Er2-xFe14+2xSi3

111112

1 g 002

1 21 2

acos and )(sin2)(cos 1

11111

11111

00

20

211111 g

gg

K. Ruebenbauer, Physica B 172, 346 (1991)

Er2-xFe14+2xSi3 powder sample

verage angle between c-axis and

iron hyperfine fields

0.5

Er2-xFe14+2xSi3 single-crystal

4f

6g

12j or 12k

12k or 12j

2b 4e

Contribution from iron atoms with hyperfine field perpendicular to c-axis

C

ontr

ibut

ion

(at.

% F

e)

Er2-xFe14+2xSi3

Conclusions

Spin reorientation from the [a - b] plane onto the c-axis occurs for all iron sub-lattices except for iron dumbbells substituting erbium (2b)

in the temperature range 130 – 80 K due to the domain flip mechanism.

Spin reorientation is less perfect for the sub-lattices (12j) and (12k) containing silicon.

Gradual second spin reorientation occurs below 50 K leading to the partial recovery of the high temperature spin structure.