Large spontaneous exchange bias in a weak ferromagnet Pb6Ni9(TeO6)5

Koteswararao, B.; Chakrabarty, Tanmoy; Basu, Tathamay; Hazra, Binoy Krishna; Srinivasarao, P. V.; Paulose, P. L.; Srinath, S.

doi:10.1038/s41598-017-09056-w

Cited by 13 publications

(6 citation statements)

References 29 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…As examples, it has been reported that Sr 4 FeRuO 8 and Sr 3 FeRuO 7 exhibits similar type of temperature dependence of magnetization with T N across 11 K and 23 K, respectively [16]. Koteswararao et al reported the presence of weak ferromagnetic moments in the antiferromagnetic state of Pb 6 Ni 9 (TeO 6 ) 5 which led to clear bifurcation between the ZFC and FC curves [17]. As noted in the Introduction, loose spins in Co 2 RuO 4 are likely due to Ru 3+ ions with spin S = 1/2 because of the weaker and random A-B coupling which we argue later is also the source of the SG state.…”

Section: Temperature Dependence Of Dc-magnetic Susceptibilitiesmentioning

confidence: 96%

Antiferromagnetism, spin-glass state, H–T phase diagram, and inverse magnetocaloric effect in Co₂RuO₄

Ghosh

Joshi

Pramanik

et al. 2020

J. Phys.: Condens. Matter

View full text Add to dashboard Cite

Static and dynamic magnetic properties of normal spinel Co2RuO4 = (Co2+) are reported based on our investigations of the temperature (T), magnetic field (H) and frequency (f) dependence of the ac-magnetic susceptibilities and dc-magnetization (M) covering the temperature range T = 2 K–400 K and H up to 90 kOe. These investigations show that Co2RuO4 exhibits an antiferromagnetic (AFM) transition at TN ∼ 15.2 K, along with a spin-glass state at slightly lower temperature (TSG) near 14.2 K. It is argued that TN is mainly governed by the ordering of the spins of Co2+ ions occupying the A-site, whereas the exchange interaction between the Co2+ ions on the A-site and randomly distributed Ru3+ on the B-site triggers the spin-glass phase, Co3+ ions on the B-site being in the low-spin non-magnetic state. Analysis of measurements of M (H, T) for T < TN are used to construct the H–T phase diagram showing that TSG shifts to lower T varying as H2/3.2 expected for spin-glass state whereas TN is nearly H-independent. For T > TN, analysis of the paramagnetic susceptibility (χ) vs. T data are fit to the modified Curie–Weiss law, χ = χ0 + C/(T + θ), with χ0 = 0.0015 emu mol−1Oe−1 yielding θ = 53 K and C = 2.16 emu-K mol−1Oe−1, the later yielding an effective magnetic moment μeff = 4.16 μB comparable to the expected value of μeff = 4.24 μB per Co2RuO4. Using TN, θ and high temperature series for χ, dominant exchange constant J1/kB ∼ 6 K between the Co2+ on the A-sites is estimated. Analysis of the ac magnetic susceptibilities near TSG yields the dynamical critical exponent zν = 5.2 and microscopic spin relaxation time τ0 ∼ 1.16 × 10−10 sec characteristic of cluster spin-glasses and the observed time-dependence of M(t) is supportive of the spin-glass state. Large M–H loop asymmetry at low temperatures with giant exchange bias effect (HEB ∼ 1.8 kOe) and coercivity (HC ∼ 7 kOe) for a field cooled sample further support the mixed magnetic phase nature of this interesting spinel. The negative magnetocaloric effect observed below TN is interpreted to be due to the AFM and SG ordering. It is argued that the observed change from positive MCE (magnetocaloric effect) for T > TN to inverse MCE for T < TN observed in Co2RuO4 (and reported previously in other systems also) is related to the change in sign of (∂M/∂T) vs. T data.

show abstract

Section: Temperature Dependence Of Dc-magnetic Susceptibilitiesmentioning

confidence: 96%

Antiferromagnetism, spin-glass state, H–T phase diagram, and inverse magnetocaloric effect in Co₂RuO₄

Ghosh

Joshi

Pramanik

et al. 2020

J. Phys.: Condens. Matter

View full text Add to dashboard Cite

show abstract

“…Although nanostructured Mn‐doped MoS 2 with a grain size of a few nanometers has shown multiple magnetic phases, [ 12 ] this possibly originates from defects or Mn‐clustering in such a disordered system, thus hindering the potential applications for magnetic refrigeration cycles and exchange bias modulation. [ 15–18 ] To the best of our knowledge, no multiple magnetic phases in 2D single crystals have been reported. In this study, we explore the magnetic properties of Mn‐doped SnS 2 single crystals with different Mn‐doping concentrations.…”

Section: Introductionmentioning

confidence: 99%

Multiple Magnetic Phases in Van Der Waals Mn‐Doped SnS₂ Semiconductor

Bouzid

Sahoo

Yun

et al. 2021

Adv Funct Materials

View full text Add to dashboard Cite

2D van der Waals magnetic semiconductors have emerged along with the possibilities of achieving an efficient gate tunability and a proximity effect with a high magnetic anisotropy compared with 3D counterparts. Little explored are multiple magnetic phases with a single crystallographic phase. Herein, the multiple magnetic phases in a Mn-doped SnS 2 single crystal with different doping concentrations using a one-step self-flux method are reported. Two ferromagnetic phases with a canted spin direction exist regardless of the Mn-doping concentration at up to 5 at%. Antiferromagnetism coexists with the ferromagnetic order and strengthens at high Mn-doping concentrations. A magnetoresistance measurement conducted on a 2 at% Mn-SnS 2 flake exhibits a positive-to-negative crossover with a value of as high as 50% and clear anisotropy, confirming the presence of ferromagnetic order in the material. By revealing multiple magnetic phases in Mn-doped SnS 2 , the study broadens the scope of state-of-the-art research on layered magnetic semiconductors.

show abstract

“…In this context we became interested in phase formation studies of lead(II) oxotellurates that additionally contain divalent first‐row transition metal cations with unpaired electrons, because this may result in new (non‐centrosymmetric) compounds and with interesting magnetic properties, as exemplified by Pb 6 Ni 9 (TeO 6 ) 5 that crystallizes in space group type P 6 3 22 and shows a large spontaneous magnetic exchange bias . Focusing on lead(II) copper(II) oxotellurates, only three phases have been structurally characterized up to date in the Pb/Cu/Te/O system, viz.…”

Section: Introductionmentioning

confidence: 99%

Phase Formation Studies of Lead(II) Copper(II) Oxotellurates: The Crystal Structures of Dimorphic PbCuTeO₅, PbCuTe₂O₆, and [Pb₂Cu₂(Te₄O₁₁)](NO₃)₂

Weil

Shirkhanlou

Stürzer

2018

Zeitschrift anorg allge chemie

View full text Add to dashboard Cite

Two modifications of the oxotellurate(VI) PbCuTeO 5 were isolated as single crystals from product mixtures obtained from solid state reactions, whereas single crystals of the oxotellurates(IV) PbCuTe 2 O 6 and [Pb 2 Cu 2 (Te 4 O 11 )](NO 3 ) 2 were grown under hydrothermal conditions. The crystal structures of all compounds comprise of characteristic coordination polyhedra, viz. nearly square [CuO 4 ] plaquettes for divalent copper, octahedral [TeO 6 ] units for hexavalent tellurium, trigonal-pyramidal [TeO 3 ] and bisphenoidal [TeO 4 ] groups for tetravalent tellurium, and distorted [PbO x ] polyhedra for divalent lead. * Prof. Dr. M. Weil E-Mail: Matthias.Weil@tuwien.ac.at [a] ARTICLE Experimental Section Crystal Growth StudiesPbCuTeO 5 : PbCuTeO 5 was obtained via solid state reactions of Cu(NO 3 ) 2 ·2.5H 2 O (0.232 g), Pb(NO 3 ) 2 (0.334 g), and H 6 TeO 6 (0.229 g) (molar ratio 1:1:1). The starting materials were weigthed, homogenously mixed by grinding, and transferred into ceramic crucibles. The open cruicibles were placed in a furnace under the following temperature/time conditions under atmospheric conditions: t 1 = 300 min [25 Ǟ 800°C], t 2 = 3000 min [800°C] and t 3 = 1000 min [800 Ǟ 25°C]. The solid product was evaluated under a polarizing microscope to choose turquoise crystals of PbCuTeO 5 with unspecific forms for the diffraction experiments. Two different modifications of PbCuTeO 5 [monoclinic (1), triclinic (2)] could be identified by singlecrystal X-ray diffraction. According to the results of X-ray powder diffraction measurements of the bulk material, Pb 2 TeO 5 (mineral name ottoite) [6,19] was identified as the major phase and monoclinic PbCuTeO 5 as a side product.

show abstract

Large spontaneous exchange bias in a weak ferromagnet Pb6Ni9(TeO6)5

Cited by 13 publications

References 29 publications

Antiferromagnetism, spin-glass state, H–T phase diagram, and inverse magnetocaloric effect in Co₂RuO₄

Antiferromagnetism, spin-glass state, H–T phase diagram, and inverse magnetocaloric effect in Co₂RuO₄

Multiple Magnetic Phases in Van Der Waals Mn‐Doped SnS₂ Semiconductor

Phase Formation Studies of Lead(II) Copper(II) Oxotellurates: The Crystal Structures of Dimorphic PbCuTeO₅, PbCuTe₂O₆, and [Pb₂Cu₂(Te₄O₁₁)](NO₃)₂

Contact Info

Product

Resources

About

Large spontaneous exchange bias in a weak ferromagnet Pb6Ni9(TeO6)5

Cited by 13 publications

References 29 publications

Antiferromagnetism, spin-glass state, H–T phase diagram, and inverse magnetocaloric effect in Co2RuO4

Antiferromagnetism, spin-glass state, H–T phase diagram, and inverse magnetocaloric effect in Co2RuO4

Multiple Magnetic Phases in Van Der Waals Mn‐Doped SnS2 Semiconductor

Phase Formation Studies of Lead(II) Copper(II) Oxotellurates: The Crystal Structures of Dimorphic PbCuTeO5, PbCuTe2O6, and [Pb2Cu2(Te4O11)](NO3)2

Contact Info

Product

Resources

About

Antiferromagnetism, spin-glass state, H–T phase diagram, and inverse magnetocaloric effect in Co₂RuO₄

Antiferromagnetism, spin-glass state, H–T phase diagram, and inverse magnetocaloric effect in Co₂RuO₄

Multiple Magnetic Phases in Van Der Waals Mn‐Doped SnS₂ Semiconductor

Phase Formation Studies of Lead(II) Copper(II) Oxotellurates: The Crystal Structures of Dimorphic PbCuTeO₅, PbCuTe₂O₆, and [Pb₂Cu₂(Te₄O₁₁)](NO₃)₂