Pressure effect on the double-exchange ferromagnet<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mrow><mml:msub><mml:mrow><mml:mi mathvariant="normal">La</mml:mi></mml:mrow><mml:mrow><mml:mn>1</mml:mn><mml:mi mathvariant="normal">−</mml:mi><mml:mi mathvariant="italic">x</mml:mi></mml:mrow></mml:msub></mml:mrow></mml:math><mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mrow><mml:msub><mml:mrow><mml:mi mathvariant="normal">Sr</mml:mi></mml:mrow><

Moritomo, Yutaka; Asamitsu, A.; Tokura, Y.

doi:10.1103/physrevb.51.16491

Cited by 256 publications

(115 citation statements)

References 3 publications

Supporting

Mentioning

101

Contrasting

Order By: Relevance

“…1 where the first-order transition changes to a second-order one. Both methods efficiently vary the effective one-electron bandwidth of these materials as either the increase of the average ionic radius [6,9,10,11,12] or the application of pressure [13,14,15] causes the enhancement of the double exchange interaction responsible for the FM phase. We also investigate the effect of magnetic field on the FM transition and determine the T C (H) phase boundary at each pressure.…”

Section: Pacs Numbersmentioning

confidence: 99%

Multicritical End Point of the First-Order Ferromagnetic Transition in Colossal Magnetoresistive Manganites

et al. 2008

Self Cite

View full text Add to dashboard Cite

We have studied the bandwidth-temperature-magnetic field phase diagram of RE0.55Sr0.45MnO3 colossal magnetoresistance manganites with ferromagnetic metallic (FM) ground state. The bandwidth (or equivalently the double exchange interaction) was controlled both via chemical substitution and hydrostatic pressure with a focus on the vicinity of the critical pressure p * where the character of the zero-field FM transition changes from first to second order. Below p * the first-order FM transition extends up to a critical magnetic field, Hcr. It is suppressed by pressure and approaches zero on the larger bandwidth side where the surface of the first-order FM phase boundary is terminated by a multicritical end-point (p * ≈32 kbar, T * ≈188 K, H * =0). The change in the character of the transition and the decrease of the CMR effect is attributed to the reduced CO/OO fluctuations. PACS numbers:Perovskite-type manganites exhibit various fundamental phenomena of current interest including colossal magnetoresistance (CMR), photo-and current-induced insulator to metal transition, first-order ferromagnetic transition and gigantic magneto-electric effect [1]. Most of them are collective effects arising from the strong interplay among the electronic degrees of freedom in the spin, charge and orbital sector which are further coupled to the underlying lattice. One of the most dramatic phase transformations induced by external stimuli is the magnetic field driven paramagnetic insulator (PI) to FM transition. It is observed in a broad range above the Curie temperature and the huge resistivity change associated with the transition is termed as colossal magnetoresistance. In the context of the CMR effect and the orbital order-disorder transition in manganites, the possibility that the first-order nature of phase transitions in three dimensional systems can be preserved in the presence of disorder has recently attracted much interest [2].Although the detailed mechanism of the CMR effect is still under debate, some of the basic ingredients have already been clarified. Among them the phase competition between the two robust neighboring states, i.e. the charge-and orbital-ordered insulator (CO/OO) and the ferromagnetic metal, is thought to be indispensable [1,3]. In the bandwidth-temperature (w − T ) phase diagram of CMR mangnites with low quenched disorder, these two phases are separated by a first-order phase boundary which can extend to as high temperature as T ≈ 200 K (see Fig. 1). It is terminated by a bicritical point where the CO/OO and FM transition line (T CO (w) and T C (w), respectively) meet each other. The temperature-induced transition from the high-temperature PI phase to the long-range ordered states on the both sides close to the bicritical point is of first order [4,5,6]. If quenched disorder is introduced to the lattice by alloying rare earth (RE) and alkali earth (AE) atoms on the A-sites with different ionic radius, the phase diagram is strongly modified; the bicritical point is suppressed and a spin-glass state appe...

show abstract

Section: Pacs Numbersmentioning

confidence: 99%

Multicritical End Point of the First-Order Ferromagnetic Transition in Colossal Magnetoresistive Manganites

et al. 2008

Self Cite

View full text Add to dashboard Cite

show abstract

“…The La 1-x Ba x MnO 3 compounds have a high concentration of vacancies in both A (La/ Ba) and B (Mn) sites, which gives rise to large localized distortions, influencing the physical properties of the material [7][8][9][10][11] . It has been shown that in samples of type La 2/3 Ba 1/3 MnO 3 the crystal-structure parameters such as mean bond length <Mn -O> and the mean bond angle <Mn -O -Mn> are factors determining the properties of the manganites 12,13 . Usually this variation leads to an increase in electron bandwidth that can strongly modify the Curie temperature and the metal-to-insulator transition temperature as well as decreasing the resistivity 12,13 .…”

Section: Introductionmentioning

confidence: 99%

“…It has been shown that in samples of type La 2/3 Ba 1/3 MnO 3 the crystal-structure parameters such as mean bond length <Mn -O> and the mean bond angle <Mn -O -Mn> are factors determining the properties of the manganites 12,13 . Usually this variation leads to an increase in electron bandwidth that can strongly modify the Curie temperature and the metal-to-insulator transition temperature as well as decreasing the resistivity 12,13 . Reported studies in the literature show that manganite properties such as insulator to metal transition temperature T IM , Curie temperature (T C ), charge ordering (CO) and magnetization can have a strong dependence on an applied hydrostatic pressure [13][14][15][16][17] .…”

Section: Introductionmentioning

confidence: 99%

Influence of Pellet Compaction Pressure on the Physical Properties of La0.7Ba0.3MnO3 Manganite

et al. 2017

View full text Add to dashboard Cite

Perovskite manganite La 0.7 Ba 0.3 MnO 3 , synthesized by ionic coordination reaction method (ICR) was compacted into pellets under different compaction pressures (P c ) and sintered at a temperature of 1150°C for 10h under a flow of O 2 . X-ray diffraction (XRD) data reveal that the samples can present simultaneously two phases -a rhombohedral structure with space group R3c and an orthorhombic structure with space group Pnma. Scanning electron microscopy (SEM) images show that, for this sintering temperature, the particle size and shape can be modified depending on the compaction pressure (P c ). Magnetization measurements show that the saturation magnetization and Curie temperature increase with P c . The enhancement of the ferromagnetic properties of perovskite manganites La 0.7 Ba 0.3 MnO 3 as a function of the compaction pressure is explained by an increase in the rhombohedral/orthorhombic structure ratio caused by this effect.

show abstract

“…Due to the strong interactions between the charge and orbital degrees of freedom, these properties can be manipulated by a number of different parameters, including external pressure 8 , oxygen stoichiometry 9 , and the doping level. 10,11 With thin films, the epitaxial strain imposed from the underlying substrate provides an additional tuning parameter for the functional properties. It has been shown that coherently strained LSMO thin films can be grown on a wide range of different single crystal oxide substrates and that the resulting strain dramatically impacts the magnetic and magnetotransport properties of the thin films.…”

mentioning

confidence: 99%

Strain engineering to control the magnetic and magnetotransport properties of La0.67Sr0.33MnO3 thin films

Yang

Kemik

Biegalski

et al. 2010

Applied Physics Letters

View full text Add to dashboard Cite

This work studies the control of the magnetic and magnetotransport properties of La 0.67 Sr 0.33 MnO 3 thin films through strain engineering. The strain state is characterized by the tetragonal distortion (c/a ratio), which can be varied continuously between a compressive strain of 1.005 to a tensile strain of 0.952 by changing the type of substrate, the growth rate, and the presence of an underlying La 0.67 Sr 0.33 FeO 3 buffer layer. Increasing tensile tetragonal distortion of the La 0.67 Sr 0.33 MnO 3 thin film decreases the saturation magnetization, changes the temperature dependence of the resistivity and magnetoresistance, and increases the resistivity by several orders of magnitude.The perovskite oxides have been widely investigated in recent years since they possess various important physical properties such as ferromagnetism, superconductivity, and ferroelectricity. 1 In particular, La 0.67 Sr 0.33 MnO 3 (LSMO) is an attractive candidate for spintronic devices 2,3 because it displays colossal magnetoresistance (CMR) and half-metallicity, and possesses a Curie temperature, T C, above room temperature (~ 360 K). 4,5 In this material, the T C marks the transition between the ferromagnetic (FM)/ metallic and the paramagnetic (PM)/ insulating states, as well as the peak in the CMR. This correlation between the electrical and magnetic properties is explained by the double-exchange mechanism 6,7 which involves the hopping of electrons between Mn 3+ and Mn 4+ ions with parallel spin through a bridging O 2-ion. Due to the strong interactions between the charge and orbital degrees of freedom, these properties can be manipulated by a number of different parameters, including external pressure 8 , oxygen stoichiometry 9 , and the doping level. 10,11 With thin films, the epitaxial strain imposed from the underlying substrate provides an additional tuning parameter for the functional properties. It has been shown that coherently strained LSMO thin films can be grown on a wide range of different single crystal oxide substrates and that the resulting strain dramatically impacts the magnetic and magnetotransport properties of the thin films. [12][13][14][15][16] The strain state can be characterized by the tetragonal distortion, defined as the c/a ratio, where the in-plane lattice parameter of the film, a, is dictated by the lattice parameter of the substrate, and the out-of-plane lattice parameter, c, is allowed to respond accordingly. For example, Kwon et al. reported that an in-plane easy magnetization direction is observed in tensile-strained films (c/a ratio < 1) grown on (001)-oriented SrTiO 3 (STO) substrates, while compressively strained films (c/a ratio > 1) grown on (001)-oriented LaAlO 3 (LAO) substrates exhibit an out-of-plane easy axis. 12 Furthermore, it has been shown that the magnitude of this tetragonal distortion depends on the crystallographic orientation of the film and the substrate. 13,14,17 Fully strained LSMO films grown on (110)-oriented substrates show enhanced electrical and magnetic propertie...

show abstract

Pressure effect on the double-exchange ferromagnetLa1−xSr<

Cited by 256 publications

References 3 publications

Multicritical End Point of the First-Order Ferromagnetic Transition in Colossal Magnetoresistive Manganites

Multicritical End Point of the First-Order Ferromagnetic Transition in Colossal Magnetoresistive Manganites

Influence of Pellet Compaction Pressure on the Physical Properties of La0.7Ba0.3MnO3 Manganite

Strain engineering to control the magnetic and magnetotransport properties of La0.67Sr0.33MnO3 thin films

Contact Info

Product

Resources

About