Unconventional magnetic transitions in the mineral clinoatacamite<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mrow><mml:msub><mml:mi mathvariant="normal">Cu</mml:mi><mml:mn>2</mml:mn></mml:msub><mml:mi mathvariant="normal">Cl</mml:mi><mml:msub><mml:mrow><mml:mo>(</mml:mo><mml:mi mathvariant="normal">O</mml:mi><mml:mi mathvariant="normal">H</mml:mi><mml:mo>)</mml:mo></mml:mrow><mml:mn>3</mml:mn></mml:msub></mml:mrow></mml:math>

鄭, 旭光; Kawae, Tatsuya; Kashitani, Y.; Li, C. S.; Tateiwa, Naoyuki; Takeda, Kazuyoshi; Yamada, Hiroshi; Xu, Chao‐Nan; Ren, Yang

doi:10.1103/physrevb.71.052409

Cited by 110 publications

(101 citation statements)

References 9 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…20). In contrast, the off-stoichiometric so-called paratacamites of formula Zn x Cu 4 − x (OH) 6 Cl 2 assume partly frozen states at LT, with two magnetic transitions finally observed at 18.1 and 6.5 K for the end member (x = 0), clinoatacamite 4,[21][22][23] . The tendency to magnetic order in paratacamites may be induced by interplane couplings through Cu defect spins at the Zn site between the kagomé layers, as well as the likely presence of a sizable Dzyaloshinsky-Moriya term.…”

Section: Discussionmentioning

confidence: 99%

Orbital switching in a frustrated magnet

et al. 2012

View full text Add to dashboard Cite

The orbital is one of the four fundamental degrees of freedom in a solid, besides spin, charge and lattice. In transition metal compounds, it is usually the d orbitals which play deciding roles in determining the crystallographic and physical properties. Here we report the discovery of a unique structural transition in single crystals of the spin-1/2 quasi-kagomé antiferromagnet volborthite, Cu 3 V 2 o 7 (oH) 2 ·2H 2 o, whereby the unpaired electron 'switches' from one d orbital to another upon cooling. This is not a conventional orbital order-disorder transition, but rather an orbital switching that has not previously been observed. The structural transition is found to profoundly affect the magnetic properties of volborthite, because magnetic interactions between Cu spins in the kagomé lattice are considerably modified by the orbital switching. This finding provides us with an interesting example to illustrate the intimate interplay between the orbital degree of freedom and competing magnetic interactions in a frustrated magnet.

show abstract

Section: Discussionmentioning

confidence: 99%

Orbital switching in a frustrated magnet

et al. 2012

View full text Add to dashboard Cite

show abstract

“…13,17 In Fig. 1, we show the 16-site periodic cluster of the pyrochlore lattice that we will use in ED.…”

Section: Approximate Models For Clinoatacamitementioning

confidence: 99%

“…13 These sites are distinguished primarily through the Cu-O-Cu bond angle, with an average angle of about 96 • for bonds involving a Cu1 site and an average angle of about 118 • for bonds within the Cu2-Cu3 distorted kagomé plane. (While the distorted lattice structure leads to some further variation within these averages, the differences are small compared to the difference in average angles for the in-plane and between plane cases.)…”

Section: Approximate Models For Clinoatacamitementioning

confidence: 99%

“…Others have suggested a pyrochlore structure with significant couplings of all Cu spins. 13,17 Susceptibility and specific heat measurements display two transitions upon cooling, at T c2 = 18 K and T c1 ≈ 6.4 K. Long range magnetic order 16,19 and a weak ferromagnetic moment are present below T c1 . For temperatures T c1 < T < T c2 muon oscillations are observed 14 suggesting a static local moment, which was originally attributed to Néel order, while neutron diffraction experiments find no sign of ordering in this temperature range, and the specific heat anomaly at T c2 is too small for the entropy change expected at an ordering transition.…”

mentioning

confidence: 99%

“…The mineral is the extension of the Zn-paratacamite family to x = 0, with the monoclinic distortion that occurs for x < 0.3. Clinoatacamite has drawn attention in recent years [13][14][15][16][17][18] in part due to its unique pyrochlore structure and in part due to the still unexplained nature of successive phase transitions. Some studies 15,18 have described the lattice as consisting of distorted kagomé layers coupled weakly through triangular layers of out-of-plane spins.…”

mentioning

confidence: 99%

See 2 more Smart Citations

Numerical study of the thermodynamics of clinoatacamite

2012

View full text Add to dashboard Cite

We study thermodynamic properties of the clinoatacamite compound, Cu2(OH)3Cl, by considering several approximate models. They include, the Heisenberg model on (i) the uniform pyrochlore lattice, (ii) a very anisotropic pyrochlore lattice, and (iii) a kagomé lattice weakly coupled to spins that sit on a triangular lattice. We utilize exact diagonalization of small clusters with periodic boundary conditions and implement a numerical linked-cluster expansion approach for quantum lattice models with reduced symmetries, which allows us to solve model (iii) in the thermodynamic limit. We find a very good agreement between the experimental uniform susceptibility and the numerical results for models (ii) and (iii), which suggest a weak ferromagnetic coupling between the kagomé and triangular layers in clinoatacamite. We also study these thermodynamic quantities in a geometrical transition between a planar pyrochlore lattice and the kagomé lattice.

show abstract

Unconventional Hole Doping of S = ½ Kagome Antiferromagnet CoCu₃(OH)₆Cl₂

Mandal,

Ninawe,

Ananthram

et al. 2024

Advanced Physics Research

View full text Add to dashboard Cite

Geometrically perfect S = ½ kagome lattices with frustrated magnetism are typically electrical insulators. Electron or hole doping is predicted to induce an exotic conducting state including superconductivity. Herein, an unconventional strategy of doping an S = ½ kagome lattice CoCu3(OH)6Cl2 is adopted – a structural analogue of a well‐known quantum spin liquid (QSL) candidate herbertsmithite (ZnCu3(OH)6Cl2) – by integrating it with reduced graphene oxide (rGO) via in situ redox chemistry. Such an integration drastically enhances the electrical conductivity, resulting in the transformation of an insulator to a semiconductor, corroborating the respective density of states obtained from the density functional theory calculations. Estimation of the magnetic moments, data on the Hall‐effect measurements, Bader charge analysis, and photoemission signals, altogether provide a bold signature of remote hole doping in CoCu3(OH)6Cl2 by rGO. The remote doping provides an alternative to the site doping approach to impart exotic electronic properties in spin liquid candidates, specifically, the generation of topological states like Dirac metal is envisioned.

show abstract

Unconventional magnetic transitions in the mineral clinoatacamiteCu2Cl(OH)3

Cited by 110 publications

References 9 publications

Orbital switching in a frustrated magnet

Orbital switching in a frustrated magnet

Numerical study of the thermodynamics of clinoatacamite

Unconventional Hole Doping of S = ½ Kagome Antiferromagnet CoCu₃(OH)₆Cl₂

Contact Info

Product

Resources

About

Unconventional magnetic transitions in the mineral clinoatacamiteCu2Cl(OH)3

Cited by 110 publications

References 9 publications

Orbital switching in a frustrated magnet

Orbital switching in a frustrated magnet

Numerical study of the thermodynamics of clinoatacamite

Unconventional Hole Doping of S = ½ Kagome Antiferromagnet CoCu3(OH)6Cl2

Contact Info

Product

Resources

About

Unconventional Hole Doping of S = ½ Kagome Antiferromagnet CoCu₃(OH)₆Cl₂