Influence of an external magnetic field on the reentrant spin-glass transition temperature in a<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mrow><mml:msub><mml:mrow><mml:mi mathvariant="normal">Cr</mml:mi></mml:mrow><mml:mrow><mml:mn>75</mml:mn></mml:mrow></mml:msub></mml:mrow></mml:math><mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mrow><mml:msub><mml:mrow><mml:mi mathvariant="normal">Fe</mml:mi></mml:mrow><mml:mrow><mml:mn>25</mml:mn></mm

Journal of Applied Physics

Felner

Tsindlekht

2019

In-field DC and AC magnetization measurements were carried out on a sigma-phase Fe55Re45 intermetallic compound aimed at determination of the magnetic phase diagram in the H-T plane. Field cooled, MFC, and zero-field cooled, MZFC, DC magnetization curves were measured in the magnetic field, H, up to 1200 Oe. AC magnetic susceptibility measurements were carried out at a constant frequency of 1465 Hz under DC fields up to H=500 Oe. The obtained results provide evidences for re-entrant magnetism in the investigated sample. The magnetic phase diagrams in the H-T plane have been outlined based on characteristic temperatures determined from the DC and AC measurements. The phase diagrams are similar yet not identical. The main difference is that in the DC diagram constructed there are two cross-over transitions within the strong-irreversibility spin-glass state, whereas in the AC susceptibility based diagram only one transition is observed. The border lines (irreversibility, cross-over) can be described in terms of the power laws.

supporting

confidence: 87%

mentioning

confidence: 56%

Magnetic phase diagram of sigma-phase Fe55Re45 compound in the H-T coordinates

Journal of Applied Physics

Felner

Tsindlekht

2019

“…Examples of the ATline are numerous e. g. [13,14], those of the GT-line are more rare e. g. [15,16], and the line with  =1 was reported twice [12,17]. The MFT predicts two critical lines in Heisenberg SGs.…”

mentioning

confidence: 99%

“…Three different predictions concerning the value of  and thus the T SG -H relationships are identified throughout the literature: (1) =2/3 known as the Almeida-Thouless (AT) line [10], (2)  =2 known as the Gabay-Toulouse (GT) line [11], and (3)  =1 [12]. Examples of the ATline are numerous e. g. [13,14], those of the GT-line are more rare e. g. [15,16], and the line with  =1 was reported twice [12,17].…”

mentioning

confidence: 99%

Magnetic phase diagrams in the H-T plane of the magnetically strongest sigma-phase Fe-V compounds

Sikora

Journal of Magnetism and Magnetic Materials

2017

Magnetization measurements were performed on two sigma-phase samples of Fe 100-x V x (x=35.5, 34.1) vs. temperature, T, and in DC magnetic field, of various amplitudes. Using three characteristic temperatures, magnetic phase diagrams in the H-T plane have been designed testifying to a re-entrant character of magnetism. The ground magnetic state, a spin glass (SG), was evidenced to be composed of two sub phases: one with a weak irreversibility and the other with a strong irreversibility. Two critical lines were reconstructed within the SG state. Both of them show a crossover from the Gabay-Toulouse behavior (low field) to a linear and/or quasi-Almeida-Touless behavior. A strong difference in the effect of the applied magnetic field on the SG phase in the two samples was revealed.

“…Five characteristic temperatures, T 1 , T 2 , T 3 , T 4 and T 5 can be deduced from the AC susceptibility measurements. Namely, T 1, T 2 as position of the peaks in the real part 15 of the AC curves ( Fig. 10), T 3 the position of the peak in the imaginary part of the susceptibility, T 4 and T 5 positions of the minima in the temperature derivative of the real part of the susceptibilitysee the inset in Fig.…”

Section: Characteristic Temperaturesmentioning

confidence: 99%

On the magnetic phase diagram of a sigma-phase Fe47Re53 compound in the H-T plane

Journal of Magnetism and Magnetic Materials

Tsindlekht

Felner

2019

Sigma-phase Fe 47 Re 53 compound was investigated by means of in-field DC and AC magnetization measurements. Field cooled, M FC , and zero-field cooled, M ZFC , DC magnetization curves were recorded in the magnetic field, H, up to 1000 Oe. AC magnetization measurements were performed at the constant frequency of 1465 Hz in the field up to H=500 Oe. Both types of measurements gave evidence in favor of a re-entrant character of magnetism in the studied sample. Based on characteristic temperatures determined from the measurements magnetic phase diagrams have been outlined in the H-T plane. The diagrams are similar but not identical. The main difference is that in the diagram constructed based on the DC data there is an intermediate antiferromagnetic-like phase which is absent in the AC diagram.Furthermore, the border lines (irreversibility, cross-over and Curie temperature) follow the power law but with correspondingly different exponents. The studied sample was also characterized by determining the effect of H on the degree of irreversibility and that of frustration.