Structural modulation of spinel ZnCr2Se4 in the vicinity of antiferromagnetic phase transition induced by an applied magnetic field

2003 ◽  
Vol 236 (1) ◽  
pp. 209-218 ◽  
Author(s):  
M. Hidaka ◽  
M. Yoshimura ◽  
S. Takahasi ◽  
S. Watanabe ◽  
J. Akimitsu
Keyword(s):  
Magnetic Field ◽  
Phase Transition ◽  
Applied Magnetic Field ◽  
Antiferromagnetic Phase ◽  
Structural Modulation

scholarly journals Намагниченность и гигантское магнетосопротивление поликристаллов TbSb при низких температурах

2019 ◽  
Vol 61 (8) ◽  
pp. 1470
Author(s):  
М.П. Волков ◽  
Н.Н. Степанов
Keyword(s):  
Magnetic Field ◽  
Phase Transition ◽  
Antiferromagnetic Phase ◽  
Positive Magnetoresistance ◽  
The Magnetic Field

On the terbium antimonide TbSb polycrystals, the dependences of the magnetization M and the resistance R on the temperature T in the range of 2 ÷ 300 K and on the magnetic field H up to H = 14 T have been studied. On the dependences M (H) at each temperature, a feature (kink) was observed associated with the metamagnetic phase transition. Giant positive magnetoresistance of TbSb in the region of the antiferromagnetic phase has been found.

scholarly journals Skyrmion Crystals and Phase Transitions in Magneto-Ferroelectric Superlattices: Dzyaloshinskii–Moriya Interaction in a Frustrated J1 − J2 Model

Symmetry ◽  
2019 ◽  
Vol 12 (1) ◽  
pp. 26 ◽  
Author(s):  
Ildus F. Sharafullin ◽  
Hung T. Diep
Keyword(s):  
Magnetic Field ◽  
Phase Transition ◽  
Applied Magnetic Field ◽  
Nearest Neighbor ◽  
Lattice Structure ◽  
Magnetic Layer ◽  
Steepest Descent Method ◽  
Spin Configuration ◽  
Dm Interaction ◽  
Ferroelectric Layer

The formation of a skyrmion crystal and its phase transition are studied, taking into account the Dzyaloshinskii–Moriya (DM) interaction at the interface between a ferroelectric layer and a magnetic layer in a superlattice. Frustration is introduced in both magnetic and ferroelectric films. The films have a simple cubic lattice structure. The spins inside the magnetic layers are Heisenberg spins interacting with each other via nearest-neighbor (NN) exchange J m and next-nearest-neighbor (NNN) exchange J 2 m . The polarizations in the ferroelectric layers are assumed to be of Ising type with NN and NNN interactions J f and J 2 f . At the magnetoelectric interface, a DM interaction J m f between spins and polarizations is supposed. The spin configuration in the ground state is calculated by the steepest descent method. In an applied magnetic field H perpendicular to the layers, we show that the formation of skyrmions at the magnetoelectric interface is strongly enhanced by the frustration brought about by the NNN antiferromagnetic interactions J 2 m and J 2 f . Various physical quantities at finite temperatures are obtained by Monte Carlo simulations. We show the critical temperature, the order parameters of magnetic and ferroelectric layers as functions of the interface DM coupling, the applied magnetic field, and J 2 m and J 2 f . The phase transition to the disordered phase is studied in detail.

Stress in Spin Valve Multilayers During Antiferromagnetic Phase Transformation

1999 ◽  
Vol 594 ◽  
Author(s):  
B. J. Daniels ◽  
S. P. Bozeman ◽  
H HA
Keyword(s):  
Magnetic Field ◽  
Phase Transformation ◽  
Applied Magnetic Field ◽  
Spin Valve ◽  
Spin Valves ◽  
Face Centered Cubic ◽  
Antiferromagnetic Phase ◽  
Wafer Curvature ◽  
The Face ◽  
Face Centered

AbstractThe stresses in sputter-deposited, NiMn- and PtMn-pinned top spin valve multilayers were measured using a laser-based wafer curvature technique. As-deposited stresses were 150 to 180 MPa in compression for NiMn- and 970 to 1020 MPa in compression for PtMn-pinned spin valves. Following deposition and stress measurement, these films were annealed in an applied magnetic field of 250 Oe for 2 hours at 300°C. This anneal causes the antiferromagnetic layer to undergo a phase transformation from the face-centered cubic (fcc) to the face-centered tetragonal (fct) crystal structure. This phase transformation increases the average stresses in the spin valves to 740–800 MPa in tension for the NiMn-pinned spin valves and to 475–580 MPa for the PtMnpinned spin valves. Stress changes during the antiferromagnetic phase transformation were also observed as a function of annealing temperature and time during substrate heating, annealing, and cooling. The stress varied nearly linearly with temperature during the heating and cooling of the substrate, indicating that the bulk of the phase transformation occurs during the isothermal portion of the anneal. By monitoring stress vs time during the isothermal anneal, the progression of the antiferromagnetic phase transformation was observed. Final stress data obtained from the wafers annealed in the wafer curvature system (no applied magnetic field) are within 10% of those obtained using the magnetic annealing process.

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