Large inverse magnetic entropy changes and magnetoresistance in the vicinity of a field-induced martensitic transformation in Ni50-xCoxMn32-yFeyGa18

Pathak, Arjun K.; Dubenko, Igor; Karaca, Haluk E.; Stadler, Shane; Ali, Naushad
August 2010
Applied Physics Letters;8/9/2010, Vol. 97 Issue 6, p062505
Academic Journal
Significantly large inverse magnetic entropy changes (ΔSM) and magnetoresistance (MR) were observed at the inverse martensitic phase transitions of the Ga-based magnetic shape memory Heusler alloys: Ni50-xCoxMn32-yFeyGa18. The crystal structures of alloys were tetragonal at 300 K and the phase transition temperatures and magnetic properties were found to be correlated with the degree of tetragonal distortion. The maximum peak values of the ΔSM and MR at H=5 T were determined as ≈(+)31 J Kg-1 K-1 and ≈-21%, respectively, for x=8 and y=2. The relatively small hysteretic loss and large refrigeration capacity observed in this system make these compounds promising materials for applications.


Related Articles

  • Nonlinear electric field tuning characteristics of yttrium iron garnet–lead zirconate titanate microwave resonators. Fetisov, Y. K.; Srinivasan, G. // Applied Physics Letters;7/21/2008, Vol. 93 Issue 3, p033508 

    This report is on hysteresis and switching associated with electric field (E) tuning of ferromagnetic resonance in a bilayer of yttrium iron garnet (YIG)-lead zirconate titanate (PZT). The tuning is facilitated by piezoelectricity of PZT and mechanical bonding with YIG. For E<2 kV/cm, the...

  • Magnetic properties of Heusler compounds Ru2CrGe and Ru2CrSn. Okada, Hironari; Koyama, Keiichi; Watanabe, Kazuo; Kusakari, Yosuke; Kanomata, Takeshi; Nishihara, Hironori // Applied Physics Letters;2/11/2008, Vol. 92 Issue 6, p062502 

    We have succeeded in synthesizing the Heusler compounds Ru2CrGe and Ru2CrSn and performed magnetization measurements in high magnetic fields up to 18 T in order to investigate the magnetic properties of Ru2CrGe and Ru2CrSn. We confirmed that the compounds have an ordered Heusler L21 structure....

  • Switchable materials: An electric effect. Sato, Osamu // Nature Chemistry;Jan2010, Vol. 2 Issue 1, p10 

    The article discusses the effects of modifying the properties of materials that will bring about the construction of switches and memory devices. It states that the electrical bias has been explored which led to the formulation of materials with electrically tunable dimensions. It notes that the...

  • Self-similar distribution in “giant” magnetic flux creep. Krasnyuk, I.; Taranets, R. // Technical Physics;Oct2007, Vol. 52 Issue 10, p1247 

    The problem of magnetic field penetration into the half-space is considered in parallel geometry in an external magnetic field increasing with time in accordance with the law B(0, t, τ0 = B c 1 (1 + t/τ0) m , m ≥ 0, t ≥ 0 ( τ 0 is the time of magnetic flux redistribution...

  • Strong ferroelectric domain-wall pinning in BiFeO3 ceramics. Rojac, Tadej; Kosec, Marija; Budic, Bojan; Setter, Nava; Damjanovic, Dragan // Journal of Applied Physics;Oct2010, Vol. 108 Issue 7, p074107 

    We have studied the polarization-electric-field hysteresis, the dielectric permittivity dispersion, the piezoelectric properties, the electric-field-induced strain, and the interrelations between these properties for bismuth ferrite (BiFeO3) ceramics. The results indicate that the domain-wall...

  • OPTIMIZATION OF THE POWER TRANSFORMER TANK. PARPALA, Rathi Constantin; STANCU, Octavian; POPESCU, Diana; PUPAZA, Cristina // Annals of DAAAM & Proceedings;Jan2009, p363 

    In addition to the core and the windings, the tank is an important component of power transformers. It accommodates the core-and-coil assembly and the oil filling, weighing several tonnes. This calls for a statically secure and oil-leak-proof design, with an optimized weight. The design of the...

  • Electromagnetic fields theory of electrical machines Part II: Uniqueness theorem for time-varying electromagnetic fields in hysteretic media. Mukerji, Saurabh Kr.; Goel, Sandeep Kr.; Bhooshan, Sunil; Basu, Kartik Prasad // International Journal of Electrical Engineering Education;Apr2005, Vol. 42 Issue 2, p203 

    Conditions resulting in a unique solution of Maxwell's equations are investigated. For this purpose, time-varying electromagnetic fields in media exhibiting a linearized form of hysteresis are considered. The treatment is an extension of the uniqueness theorem for electromagnetic fields in...

  • Influence of the configuration of the magnetic field of an ion diode on the parameters of an ion beam. Stepanov, A.; Remnev, G. // Instruments & Experimental Techniques;Jul2009, Vol. 52 Issue 4, p565 

    The distribution of magnetic-field induction in the accelerating gap of an ion diode with external magnetic insulation is studied. The absence of a device for preliminary plasma production is a distinguishing feature of this diode. It is shown that a certain configuration of the magnetic field...

  • Numerical Computation of Fluid Flow in a Magnetohydrodynamic Micropump. Duwairi, H. M.; Abdullah, Mustafa // Turkish Journal of Engineering & Environmental Sciences;2008, Vol. 32 Issue 1, p1 

    A 2-dimensional model is developed to investigate fluid flow in a magneto-hydrodynamic (MHD) micropump. The transient, laminar, incompressible, and developing flow equations are numerically solved using the finite difference method and the SIMPLE algorithm. The micropump is driven using the...


Read the Article


Sorry, but this item is not currently available from your library.

Try another library?
Sign out of this library

Other Topics