Observation of transitions to spin-slip structures in single-crystal holmium

Magnetic and magnetothermal properties, and the magnetic phase diagram of single-crystal holmium along the easy magnetization direction

“…The high T lambda-like transition (Néel temperature) always remains at ∼130 K. The 30 kOe plot shows two additional peaks at ∼43 and ∼ 97 K which can be associated with the existence of the spin-slip structures. The existence of these structures in this region was supported previously by observations of slight anomalies in magnetic measurements [9]. With increasing field (figure 10(b)) the low T peak overlaps the discontinuity which is no longer seen at 90 kOe.…”

“…In the 1980s a number of new magnetic structures of Ho, such as the spin-slip phases and the helifans, were discovered [8]. Ali et al [9] have observed anomalies in the temperature dependence of the magnetization at 21, 42, and 98 K and that was, as far as we know, the first and the only time these spin-slip transitions have been detected using magnetization measurements. The theoretical study by Hughes et al [10] summed up the experimental results and the authors noted that the trend from ferromagnetism to incommensurate ordering in the lanthanide series as atomic number increases is connected with the decrease in unit cell volume.…”

Theory of Magnetic Ordering in the Heavy Rare Earths:Ab InitioElectronic Origin of Pair- and Four-Spin Interactions

“…Below its T c Gd preserves its FM order as the strength of the magnetic field applied along its easy axis is increased. This is in sharp contrast to Tb [3,[11][12][13], Dy [4][5][6][7]14] and Ho [8,10] above T t , which first distort their HAFM order (dis-HAFM) before undergoing a first order transition into a fan magnetic structure followed by a second order transition to a FM state with further increase in the magnetic field. Dy and Ho also exhibit signs of additional spin-flip and vortex transitions associated with subtle changes in measured magnetization curves.…”

Strong magnetocaloric effect induced by spin reorientation transitions in epitaxial Ho thin films

“…Ho has a commensurate conical structure below T C ~19 K and a basal-plane spiral structure between 19 K and 133 K in their helicities. Above the Néel temperature (T N ) ~133 K, Ho is paramagnetic [1][2][3][4]. Several magnetic phases (cone, fan, and helix) exist at different temperatures in zero magnetic field.…”

“…The existence of each phase is determined by two major competing energies: exchange and magneto-crystalline anisotropy. For instance, in high-purity holmium crystals the spin-slip and fan-helicoidal phases can be observed [1][2][3][4]. In [5], the region of existence of a spin-slip phase in the 95 -110 K range and an intermediate phase of the ferro-fan type in the 40 -120 K range were found under 20 -80 kOe applied magnetic field.…”