P. Steiner

Critical phenomena in Fe:Ni

Abstract Mossbauer effect measurements of Fe: Ni have been performed in the vicinity of the Curie point; they yield for the critical exponent of the magnetization β = 0.38 ± 0.01 and an exponent for the critical fluctuations which is δ = -1.0 ± 0.1.

Magnetism and superconductivity in LaEu

Abstract The phase diagram of the magnetic superconductor La Eu has been investigated by bulk susceptibility measurements and Mossbauer effect measurements up to Eu concentrations of 7 at.%. The concentration dependence of the phase separation line between the purely superconducting and the superconducting and magnetic state suggests that the magnetic order is of the spin glass type.

Impurity-impurity interactions in a very dilute Fe:Au system

Abstract An analysis of recent Mossbauer data of a very dilute Fe: Au system strongly indicates some kind of antiferromagnetic order at low temperatures and low external fields. This shows, that even at very low impurity concentrations for this system impurity-impurity interactions are dominant. So one must be very careful in extracting from the various experimental data parameters, which characterise the Kondo behavior of the single impurities in the system Fe: Au .

Observation of the interference between photoeffect and internal conversion with the 21 keV M1 Mössbauer transition of 151Eu

Abstract The interference of the photoeffect and nuclear resonance absorption followed by internal conversion has been observed for the 21 MeV M1 transition in 151Eu. The measured interference parameter is βMiexp = (0.92±0.18) × 10−2.

Study of the local susceptibility in the Fe: Au system

Abstract Mossbauer effect measurements of the Fe: Au system are reported which yield the local susceptibility of the Fe ions. At high temperatures (T ⩾ 10°K) a Curie Weiss law with θ1 = 9.8°K is observed, whereas at low temperatures the Curie Weiss temperature is θ2 = 0.45°K. In both temperature regimes the local susceptibility is a linear function of the total susceptibility. In addition below 4°K the local magnetization is a linear function of the total magnetization up to external fields of 60 kG.

The phase diagram of a magnetic superconductor

Abstract Magnetic ordering temperatures (via Mossbauer effect measurements) and superconducting transition temperatures (via mutual inductance bridge) for the system Eu x La 1− x have been measured. From the date the phase diagram of a magnetic superconductor can be deduced.

Mössbauer experiments on dilute 57Fe in Cu,Ag and Au

The local susceptibility in CuFe, AgFe and AuFe is determined from Mossbauer experiments. CuFe and AgFe show nearly the same temperature dependence‐a Curie‐Weiss law at high temperatures and a T2‐behaviour at low temperatures. In contrast in AuFe we observe two Curie‐Weiss regimes and again the T2‐behaviour at low temperatures.