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• (Mn 2 Sb) 1- x Bi x single crystals were batch-grown by an improved Bridgeman method. • Substitution of Sb by Bi leads to a shrinkage of cell volume and occurrence of the first-order transition. • Effects of chemical doping and hydrostatic pressure application were compared for the crystal with x = 0.12. • Large magnetoresistance and magnetostrain with good reversibility were attained at 120 K under 30 kOe for x = 0.12. We investigate the effects of Bi substitution on the structure, magnetization, magnetoresistance, and magnetostrain in single crystals of (Mn 2 Sb) 1- x Bi x (x = 0.06, 0.08, 0.1, and 0.12). It is found that the element Bi can be partially substituted for Sb in the tetragonal Mn 2 Sb main phase, and partially forms the MnBi and Bi-rich secondary phases. The introduction of Bi causes the simultaneous lattice shrinkages in a and c for the main phase, and also enhances the transition temperature of the first-order magnetoelastic ferrimagnetic-antiferromagnetic transition. Such an enhancement in transition temperature due to contraction of the unit-cell volume contraction is also experimentally proven based on the thermomagnetic curves under hydrostatic pressure for a crystal with × = 0.12. The volume contraction rate due to hydrostatic pressure is deduced to be −0.0386 Å3/GPa. Moreover, the highest values of in-plane magnetoresistance (∼-30%) and magnetostrain (∼−1448 ppm) with good reversibility are attained at 120 K under 30 kOe, which was proven to be the optimal magnetic field. Our experimental results show that Mn 2 Sb-based intermetallic compounds can be considered promising candidates for low-cost, multifunctional magnetic materials. [ABSTRACT FROM AUTHOR]

The influence of isotropic physical pressure, applied either during the high-pressure-high-temperature (HPHT) annealing or the measuring processes, on the magnetic properties of NdFeO 3 single crystal, has been investigated. In comparison to the complete spin reorientation (SR) in an as-grown NdFeO 3 single crystal, the thermomagnetic M (T) and isothermal M (H) curves for a HPHT-annealed sample indicates an incomplete SR transition from a Γ 2 -rich to a Γ 4 -rich Γ 24 mixed phase. Moreover, the M (T) curves of the as-grown sample under different measuring hydrostatic pressures suggest that the SR transition takes place in the sequence of Γ 2 → Γ 1 + Γ 2 + Γ 4 → Γ 1 + Γ 4 → Γ 4 , instead of the Γ 2 → Γ 2 + Γ 4 → Γ 4, without applying pressure during the measuring process. Such manipulation of the magnetic configuration reveals that the 3 d -4 f interaction in the NdFeO 3 could be greatly affected by the isotropic pressure. These findings may provide a new perspective and possibility for the tuning of the magnetism and corresponding microscopic interactions. • A comparative study of isotropic pressure on NdFeO3 single crystal is carried out. • High-pressure-high-temperature annealing leads to an incomplete spin reorientation • Hydrostatic pressure in the measuring process introduces an intermediate phase. • Isotropic pressure can tune the magnetism and microscopic interactions in NdFeO3. [ABSTRACT FROM AUTHOR]

• Spin reorientation vanishes at a high magnetic field for a TmFeO 3 single crystal. • Evidence of magneto-structural coupling in the TmFeO 3 single crystal is provided. • Spin reorientation shifts and widens under hydrostatic pressure. • Widening of spin reorientation transition is attributed to an intermediate phase. We report the growth of a TmFeO 3 single crystal, its magnetic and structural properties upon varying temperature, magnetic field, and hydrostatic pressure. The abrupt change related to the spin reorientation (SR) process vanishes under a 30 kOe magnetic field in both thermomagnetic and strain curves, indicating strong magneto-structural coupling in such orthoferrite. Interestingly, the thermomagnetic curve under hydrostatic pressure reveals that the SR shifts towards higher temperatures and its temperature interval widens upon the application of external hydrostatic pressure. Combining the strain data obtained under similar conditions, the onset temperature shift of SR is concluded to originate from changes in structural parameters and widening of the SR transition is attributed to the presence of an intermediate phase. These findings may shed light on the envisage of potential uses in magneto-mechanical and transducer devices, based on the interaction between structure and magnetism. [ABSTRACT FROM AUTHOR]