Coexistence of ferromagnetic and antiferromagnetic phases in Nd0.5CaxSr0.5−xMnO3manganites

Pillai, Sakuntala S.; Rangarajan, Govindan; Raju, N. P.; Epstein, Arthur J.; Santhosh, P. N.

doi:10.1088/0953-8984/19/49/496221

Cited by 14 publications

(11 citation statements)

References 42 publications

(62 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…This Mn 3 O 4 phase leads to the formation of short range ordered antiferromagnetic superexchange interactions between of Mn 3+ ions. The coexistence of antiferromagnetic superexchange interactions and ferromagnetic double exchange interactions of Mn 3+ /Mn 4+ ions introduces inhomogeneous exchange interactions inside some of the clusters [43][44][45]. Such heterogeneity in intra-cluster interactions is dominated over by the surface disorder in nanograin sized milled samples.…”

Section: Samplementioning

confidence: 99%

“…We understand that (T) minimum of the bulk sample appeared due to competition between weak ferromagnetic (semiconductor/insulator) grain boundaries and ferromagnetic (metallic) grains. Magnetic disorder and frustration in the ferromagnetic ground state of manganites [43][44][45] are affecting the low temperature resistivity upturn. Additional grain boundary disorder (spin canting, breaking of long ranged ferromagnetic order) is enough for the disappearance of resistivity minimum in nanocrystalline samples.…”

Section: Resistivity and Magnetoresistancementioning

confidence: 99%

See 1 more Smart Citation

Grain size dependent magnetization, electrical resistivity and magnetoresistance in mechanically milled La0.67Sr0.33MnO3

Muthuselvam

Bhowmik

2012

Journal of Alloys and Compounds

View full text Add to dashboard Cite

Section: Samplementioning

confidence: 99%

Section: Resistivity and Magnetoresistancementioning

confidence: 99%

Grain size dependent magnetization, electrical resistivity and magnetoresistance in mechanically milled La0.67Sr0.33MnO3

Muthuselvam

Bhowmik

2012

Journal of Alloys and Compounds

View full text Add to dashboard Cite

“…Rietveld analysis of the X-ray powder diffraction patterns confirms the formation of a clear single perovskite phase with an orthorhombic structure [16]. For…”

Section: Resultsmentioning

confidence: 79%

“…The experimental values of the effective paramagnetic moments are higher than the theoretical ones in all samples (see Table 2). It is the signature of clusters of Mn 4+ and Mn 3+ [16,22]. This indicates that in the paramagnetic state, the magnetic spins do not exist as individuals; they exist rather in small groups revealing the presence of ferromagnetic correlations in the paramagnetic phase.…”

Section: (T)mentioning

confidence: 97%

Effect of strontium substitution on the physical properties of Nd_0.5Ca_0.5−xSr_xMnO₃(0.0≤x≤0.5) manganites

M’nassri

Cheikhrouhou‐Koubaa

Koubàa

et al. 2012

IOP Conf. Ser.: Mater. Sci. Eng.

View full text Add to dashboard Cite

Abstract. The structural and magnetic properties of Nd 0.5 Ca 0.5-x Sr x MnO 3 (0.0≤x≤0.5) were investigated experimentally. All our samples were synthesized using the standard ceramic elaborating method at high temperatures. X-ray diffraction was systematically carried out on Nd 0.5 Ca 0.5-x Sr x MnO 3 polycrystalline compounds. All our samples crystallized in the orthorhombic system. The unit cell volume increased with increasing strontium amount. The substitution of Ca by Sr destroyed the charge order state observed in the parent compound and induced a ferromagnetic phase at low temperatures. The Curie temperature T C increased from 150 K for x=0.1 to 260 K for x=0.5. IntroductionOver the last fifteen years, perovskite manganese oxides, Ln 1-x A x MnO 3 (Ln=La, Nd, Pr, Sm,... and A=Ca, Sr, Ba, Pb,...) have known considerable attention due to the wide range of crystallographic, magnetic and magneto-transport properties they exhibit [1][2][3]. With strategic substitution of divalent ions at the A site, some of the Mn 3+ ions (3d 3 , t 3 2g e g 1 ) convert into Mn 4+ ions (3d 3 ,t 3 2g e g 0 ) [4], resulting in fascinating physical phenomena such as paramagnetic (PM) insulator to ferromagnetic (FM) metallic transition or various mixed magnetic phases canted antiferromagnetic (AFM)/spin glass (SG) coupled with charge/orbital ordered (CO/OO) states in a particular doping range. The physical properties in manganese perovskites are thought to arise from the strong competition among a ferromagnetic double-exchange interaction, an antiferromagnetic super-exchange interaction and the spin-phonon coupling [5][6][7]. These interactions are determined by intrinsic parameters such as doping level, average cationic size, cationic disorder and oxygen stoichiometry [8].Recently, extensive studies have been focused on the charge ordering (CO) and orbital ordering (OO) phase, which is most easily observed in half-doped x = 0.5 manganites [9]. The spatial CO phase behaves as the periodic arrangement of Mn 3+ /Mn 4+ ions. Generally, the CO formation is accompanied by an antiferromagnetic (AFM) phase transition. The ground state, therefore, is usually assigned to be CO/AFM state. Though the origin of the CO phase is still subject of debate, it is extensively acknowledged that the mean radius of the A-cation site plays a key role [10]. Experimentally, =1.24Å is recognized as the critical mean radius [11]. With smaller than 1.24 Å, the CO phase exists in the system; however, with larger than 1.24 Å, there is no CO phase. By way of 1 To whom any correspondence should be addressed.

show abstract

“…Recently, the phase diagrams of these compounds have shown a critical behavior involving competing spin, charge, orbital, and lattice orders, which stimulate further studies of these materials . Especially, for the half‐doped R 0.5 A 0.5 MnO 3 compounds with relatively smaller average A‐site ionic radii 〈r A 〉, an interesting CE‐type anti‐ferromagnetic (AFM) structure is presented . Both ferromagnetic (FM) and AFM interactions may coexist in the compounds, due to the coexistence of the double exchange (DE) and the super‐exchange (SE) interactions among Mn ions.…”

Section: Introductionmentioning

confidence: 99%

Study of the Effects of A‐Site La‐Substition on the Electrical and Magnetic Properties of Dy_0.5Sr_0.5MnO₃ Ceramics

Shi

Zhao

et al. 2017

Physica Status Solidi (b)

View full text Add to dashboard Cite

The Dy0.5−xLaxSr0.5MnO3 (0 ≤ x ≤ 0.4) manganite compounds have been synthesized by solid state reaction, and the effect of nonmagnetic La ion doping on the crystal structure, electrical and magnetic properties are systematically investigated. It is found that with successive substitution of La element, A‐site cationic arrangement transforms from disorder (random, x ≤ 0.25) to order structure (x > 0.25), and the crystal structure undergoes a transition from cubic to orthogonal distorted perovskite structure. When 0 ≤ x < 0.25, the compounds show a similar semiconducting behavior and magnetic property with a low‐temperature spin‐glass state. When x = 0.25, however, long‐range ferromagnetic (FM) order begins to form and coexists with anti‐ferromagnetic (AFM) phase in the compound. When x further increases, FM interactions strengthen and become predominant in the magnetic properties of the compound. On the other hand, in contrast to the semiconducting behavior of the compounds with x ≤ 0.25, when x > 0.25, the resistivity decreases quickly in the corresponding temperature range. It is suggested that not only the A‐site cationic disorder turning, closely related to the cation radius distribution (mismatch), σ2, controlled by A‐site cation radius 〈rA〉, but the substitution of nonmagnetic La ions, or A‐site magnetic change, is an effective way to adjust the crystal structure and the related magnetic and electrical properties of the perovskite manganite oxides for the applications.

show abstract

Coexistence of ferromagnetic and antiferromagnetic phases in Nd_0.5Ca_xSr_0.5−xMnO₃manganites

Cited by 14 publications

References 42 publications

Grain size dependent magnetization, electrical resistivity and magnetoresistance in mechanically milled La0.67Sr0.33MnO3

Grain size dependent magnetization, electrical resistivity and magnetoresistance in mechanically milled La0.67Sr0.33MnO3

Effect of strontium substitution on the physical properties of Nd_0.5Ca_0.5−xSr_xMnO₃(0.0≤x≤0.5) manganites

Study of the Effects of A‐Site La‐Substition on the Electrical and Magnetic Properties of Dy_0.5Sr_0.5MnO₃ Ceramics

Contact Info

Product

Resources

About

Coexistence of ferromagnetic and antiferromagnetic phases in Nd0.5CaxSr0.5−xMnO3manganites

Cited by 14 publications

References 42 publications

Grain size dependent magnetization, electrical resistivity and magnetoresistance in mechanically milled La0.67Sr0.33MnO3

Grain size dependent magnetization, electrical resistivity and magnetoresistance in mechanically milled La0.67Sr0.33MnO3

Effect of strontium substitution on the physical properties of Nd0.5Ca0.5−xSrxMnO3(0.0≤x≤0.5) manganites

Study of the Effects of A‐Site La‐Substition on the Electrical and Magnetic Properties of Dy0.5Sr0.5MnO3 Ceramics

Contact Info

Product

Resources

About

Coexistence of ferromagnetic and antiferromagnetic phases in Nd_0.5Ca_xSr_0.5−xMnO₃manganites

Effect of strontium substitution on the physical properties of Nd_0.5Ca_0.5−xSr_xMnO₃(0.0≤x≤0.5) manganites

Study of the Effects of A‐Site La‐Substition on the Electrical and Magnetic Properties of Dy_0.5Sr_0.5MnO₃ Ceramics