Anomalous transport properties of<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mrow><mml:mi mathvariant="normal">N</mml:mi><mml:msub><mml:mi mathvariant="normal">i</mml:mi><mml:mn>2</mml:mn></mml:msub><mml:mi mathvariant="normal">M</mml:mi><mml:msub><mml:mi mathvariant="normal">n</mml:mi><mml:mrow><mml:mn>1</mml:mn><mml:mo>−</mml:mo><mml:mi>x</mml:mi></mml:mrow></mml:msub><mml:mi mathvariant="normal">C</mml:mi><mml:msub><mml:mi mathvariant="normal">r</mml:mi><mml:mi>x</mml:mi></mml:msub><mm

Khan, Mahmud; Brock, Jeffrey; Sugerman, Ian

doi:10.1103/physrevb.93.054419

Cited by 25 publications

(11 citation statements)

References 38 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The value of T C for x = 0.00 (Ni 2 MnGa) has been found to be 375 K, using the same approach [16]. For 0≤x≤0.25, the premartensitic phase was observed before the martensitic transition occurred [27,28,29]. Singh et al performed X-ray measurements and demonstrated that the crystal structure of Ni 2 MnGa in the premartensitic phase was a 3M-like incommensurate structure [30].…”

Section: Resultsmentioning

confidence: 99%

The Characteristic Properties of Magnetostriction and Magneto-Volume Effects of Ni2MnGa-Type Ferromagnetic Heusler Alloys

et al. 2019

View full text Add to dashboard Cite

In this article, we review the magnetostriction and magneto-volume effects of Ni2MnGa-type ferromagnetic Heusler alloys at the martensitic, premartensitic, and austenitic phases. The correlations of forced magnetostriction (ΔV/V) and magnetization (M), using the self-consistent renormalization (SCR) spin fluctuation theory of an itinerant electron ferromagnet proposed by Takahashi, are evaluated for the ferromagnetic Heusler alloys. The magneto-volume effect occurs due to the interaction between the magnetism and volume change of the magnetic crystals. The magnetic field-induced strain (referred to as forced magnetostriction) and the magnetization are measured, and the correlation of magnetostriction and magnetization is evaluated. The forced volume magnetostriction ΔV/V at the Curie temperature, TC is proportional to M4, and the plots cross the origin point; that is, (M4, ΔV/V) = (0, 0). This consequence is in good agreement with the spin fluctuation theory of Takahashi. An experimental study is carried out and the results of the measurement agree with the theory. The value of forced magnetostriction is proportional to the valence electron concentration per atom (e/a). Therefore, the forced magnetostriction reflects the electronic states of the ferromagnetic alloys. The magnetostriction near the premartensitic transition temperature (TP) induces lattice softening; however, lattice softening is negligible at TC. The forced magnetostriction at TC occurs due to spin fluctuations of the itinerant electrons. In the martensitic and premartensitic phases, softening of the lattice occurs due to the shallow hollow (potential barrier) of the total energy difference between the L21 cubic and modulated 10M or 14M structures. As a result, magnetostriction is increased by the magnetic field.

show abstract

Section: Resultsmentioning

confidence: 99%

The Characteristic Properties of Magnetostriction and Magneto-Volume Effects of Ni2MnGa-Type Ferromagnetic Heusler Alloys

et al. 2019

View full text Add to dashboard Cite

show abstract

“…Uijttewaal et al [43] state that the contributions of both magnons and phonons to the free energy of premartensite and austenite only "slightly differ" and that the existence of the premartensitic transition results from a delicate interplay between the vibrational and magnetic excitation mechanisms. We considered that the clear variation [35]. Therefore, the martensite phase is a ferromagnetic phase.…”

Section: Resultsmentioning

confidence: 99%

“…A clear variation was observed below the premartensitic transition temperature T P , thus indicating that lattice deformation occurs below T P . The martensite-austenite phase transition was investigated for a series of 0 ≤ x ≤ 0.7 Heusler alloys by using X-ray diffraction, DC magnetisation, and electrical resistivity measurements [35]. For x < 0.20, a ferromagnetic premartensite state appeared below T P .…”

Section: Purpose Of This Studymentioning

confidence: 99%

Magnetostriction of Ni2Mn1−xCrxGa Heusler Alloys

Sakon

Fujimoto

Kanomata

et al. 2017

Metals

View full text Add to dashboard Cite

Among the functionalities of magnetic Heusler alloys, magnetostriction is attracting considerable attention. The alloy Ni 2 MnGa has a premartensite phase, which is a precursor state to the martensitic transition. Some researchers have observed magnetostriction in this alloy in the premartensite phase. We performed magnetostriction studies on the premartensite phase of related Cr-substituted Ni 2 Mn 1−x Cr x Ga alloys and measured the thermal strain, permeability, magnetisation, and magnetostriction of polycrystals. Our thermal expansion measurements show an anomaly that indicates the occurrence of lattice deformation below the premartensitic transition temperature T P . Our permeability measurements also showed an anomaly at the premartensitic transition. From our magnetisation results, we obtained the magnetic-anisotropy constant K 1 . In the martensite phase, we found that the magnetic-anisotropy constant of the x = 0.00 alloy is larger than that of the x = 0.15 alloy. At 0.24 MA/m, we obtained a magnetostriction of −120 ppm for the x = 0.15 alloy. Magnetostriction in the premartensite phase is larger than that in the austenite and martensite phases at low magnetic-field strength, thus indicating that it is related to lattice softening in the premartensite phase. The e/a is proportional to the magnetostriction and T P , which indicates that the electron energy, the magnetostriction, and the T p are correlative each other.

show abstract

“…In the stoichiometric Ni 2 MnGa alloys only a small change of resistivity was observed at temperature of M −A transition, T M −A [4]. But a pronounced change of electric resistivity of the off-stoichiometric and doped alloys was observed in the temperature range around T M −A in the Ni 2 (MnCr)Ga alloys [8]. In this paper we describe and discuss a correlation of the resistivity changes with the magnetic behavior of the alloys.…”

Section: Introductionmentioning

confidence: 94%

Spin Disordered Resistivity of the Heusler Ni₂MnGa-based Alloys

et al. 2017

View full text Add to dashboard Cite

Electrical resistivity of the selected Heusler off-stoichiometric (NiCo)2Mn(GaIn) alloys was studied in a wide range of temperature and magnetic field. A step-like change of resistivity (∆ρ ≈ 24 µΩcm) was detected in the offstoichiometric Ni1.85Mn1.21Ga0.94 alloy at temperature of martensitic structural transition. This ∆ρ is much more significant than one in the stoichiometric Ni2MnGa alloy. In the case of the off-stoichiometric (NiCo)2Mn(GaIn) alloys, an enormous change of resistivity, ∆ρ ≈ 200 µΩcm, accompanies the structural transition. Simultaneously, the maximum of the spin disordered resistivity ρ sd (T ) of austenite phase of the alloys is slightly dependent on composition of the alloy and vary from ≈ 30 µΩcm up to ≈ 45 µΩcm, in good agreement with theoretical calculations. Due to high sensitivity of the structural transition temperature of the alloys to magnetic field, the very pronounced magnetoresistance effects have been observed in the studied alloys.

show abstract

Anomalous transport properties ofNi2Mn1−xCrx

Cited by 25 publications

References 38 publications

The Characteristic Properties of Magnetostriction and Magneto-Volume Effects of Ni2MnGa-Type Ferromagnetic Heusler Alloys

The Characteristic Properties of Magnetostriction and Magneto-Volume Effects of Ni2MnGa-Type Ferromagnetic Heusler Alloys

Magnetostriction of Ni2Mn1−xCrxGa Heusler Alloys

Spin Disordered Resistivity of the Heusler Ni₂MnGa-based Alloys

Contact Info

Product

Resources

About

Anomalous transport properties ofNi2Mn1−xCrx

Cited by 25 publications

References 38 publications

The Characteristic Properties of Magnetostriction and Magneto-Volume Effects of Ni2MnGa-Type Ferromagnetic Heusler Alloys

The Characteristic Properties of Magnetostriction and Magneto-Volume Effects of Ni2MnGa-Type Ferromagnetic Heusler Alloys

Magnetostriction of Ni2Mn1−xCrxGa Heusler Alloys

Spin Disordered Resistivity of the Heusler Ni2MnGa-based Alloys

Contact Info

Product

Resources

About

Spin Disordered Resistivity of the Heusler Ni₂MnGa-based Alloys