Magnetic hysteresis scaling behavior in terbium and holmium

Abstract

Hysteresis scaling for magnetic minor loops has been examined in the heavy rare-earth metals Tb and Ho, varying the temperature and magnetic-field amplitudes. In addition to the low-temperature ferromagnetic phase below T c , the scaling law between the hysteresis loss and remanent flux density with an exponent of ∼1.3 was observed in the higher-temperature helical antiferromagnetic phase for both metals. The coefficient which reflects the pinning fields of the domain walls decreases with increasing temperature below T c , but it exhibits a sharp increase after the onset of the helical antiferromagnetic phase. The observations above T c were explained as due to the irreversible motion of spiral domain walls, unlike the 180• Bloch walls that are typical in the ferromagnetic phase.

Magnetic hysteresis scaling in thulium: Implication of irreversibility-related scaling for soliton wall motion in an Ising system

“…The fits yielded n m ¼ 1:13 7 0:02 for both heating and cooling data. This value is slightly lower than 1.25-1.33 for Dy, Tb, and Ho reported previously [5,6], but it is close to 1.0670.03 for Er [14,15]. Fig.…”

“…W 0 m monotonically decreases, exhibits a local minimum just below T c , and then sharply increases in the ICM phase with increasing temperature. This temperature dependence is similar to that for other rare earth metals [5,6,14]. Tm exhibits a strong uniaxial anisotropy and all magnetic moments are squared-up along the c-axis at low temperatures [11].…”

“…In contrast to the traditional Steinmetz equation for bulk soft ferromagnets [4], the scaling law universally holds true also for semi-hard ferromagnetic materials, in which another magnetization mechanisms (reversible wall motion, magnetization rotation) coexist with irreversible Bloch wall motion. Further, the very close exponent was quite recently obtained in the helical magnetic phase with spiral domain walls for rare-earth metals Dy, Ho, and Tb [5,6]. The results demonstrated a possible existence of a universal mechanism of irreversible wall motion, independent of the types of domain walls.…”

Thermodynamic and electrochemical properties of holmium and HoxAly intermetallic compounds in the LiCl-KCl eutectic

“…Rare earth or lanthanides (Ln) metals and their alloys have attracted great interests in recent years due to their specific functional properties such as excellent magnetic [1][2][3] and optical performances [4,5] which are extensively involved in the electronic, engineering and medical fields etc. Through electrochemical method in molten salts, Ln and their alloys can be prepared with high purity and more maneuverability [6][7][8][9].…”

Effect of disorder on 2D topological merging transition from a Dirac semi-metal to a normal insulator

“…Recently such a merging of tunable Dirac points has been realized using a degenerate Fermi gas trapped in a 2D honeycomb optical lattice [18], in photonic graphene [19] and in microwave experiments [20]. Moving and merging of two Dirac points in the organic conductor α-(BEDT-TTF) 2 I 3 has also been discussed in [7,21,22].…”