248 research outputs found
Spin liquid close to a quantum critical point in NaIrO
NaIrO is a candidate material for a 3-dimensional quantum
spin-liquid on the hyperkagome lattice. We present thermodynamic measurements
of heat capacity and thermal conductivity on high quality
polycrystalline samples of NaIrO down to mK and mK,
respectively. Absence of long-range magnetic order down to mK strongly
supports claims of a spin-liquid ground state. The constant magnetic
susceptibility below K and the presence of a small but
finite linear- term in suggest the presence of gapless spin
excitations. Additionally, the magnetic Grneisen ratio shows a
divergence as K and a scaling behavior which clearly
demonstrates that NaIrO is situated close to a zero-field QCP.Comment: 5 pages, 4 figures, PRB rapid, in pres
Giant cell tumour in the diaphysis of radius – a report
This is an Open Access article distributed under the terms of the Creative Commons Attribution Licens
Relevance of the Heisenberg-Kitaev model for the honeycomb lattice iridates A_2IrO_3
Combining thermodynamic measurements with theoretical density functional and
thermodynamic calculations we demonstrate that the honeycomb lattice iridates
A2IrO3 (A = Na, Li) are magnetically ordered Mott insulators where the
magnetism of the effective spin-orbital S = 1/2 moments can be captured by a
Heisenberg-Kitaev (HK) model with Heisenberg interactions beyond
nearest-neighbor exchange. Experimentally, we observe an increase of the
Curie-Weiss temperature from \theta = -125 K for Na2IrO3 to \theta = -33 K for
Li2IrO3, while the antiferromagnetic ordering temperature remains roughly the
same T_N = 15 K for both materials. Using finite-temperature functional
renormalization group calculations we show that this evolution of \theta, T_N,
the frustration parameter f = \theta/T_N, and the zig-zag magnetic ordering
structure suggested for both materials by density functional theory can be
captured within this extended HK model. Combining our experimental and
theoretical results, we estimate that Na2IrO3 is deep in the magnetically
ordered regime of the HK model (\alpha \approx 0.25), while Li2IrO3 appears to
be close to a spin-liquid regime (0.6 < \alpha < 0.7).Comment: Version accepted for publication in PRL. Additional DFT and
thermodynamic calculations have been included. 6 pages of supplementary
material include
Success Factors for e-Court Implementation at Allahabad High-Court
This paper is an attempt to study the important factors responsible for successful implementation of Electronic Court (e-Court) at Allahabad High Court India, to examine the effectiveness and efficiency of e-Court at Allahabad High Court and to conduct a feasibility analysis of replication of e-Court in lower courts of India. A qualitative case study approach was adopted comprising in-depth literature review and structured interview to conduct the study. Subsequently, NVivo 11 Pro software is used to analyze the recorded data and to identify the Critical Success Factors (CSFs). The findings of the study identified 23 CSFs for efficient and effective implementation of e-Court at Allahabad High Court. Also, feasibility analysis explored replication of e-Court in lower courts of India is possible after resolving few issues. The outcome will be helpful for efficient and effective implementation of e-Court in various other High Courts and lower courts of India as well as to enhance the effectiveness of process
Long range magnetic ordering in NaIrO
We report a combined experimental and theoretical investigation of the
magnetic structure of the honeycomb lattice magnet NaIrO, a strong
candidate for a realization of a gapless spin-liquid. Using resonant x-ray
magnetic scattering at the Ir L-edge, we find 3D long range
antiferromagnetic order below T=13.3 K. From the azimuthal dependence of
the magnetic Bragg peak, the ordered moment is determined to be predominantly
along the {\it a}-axis. Combining the experimental data with first principles
calculations, we propose that the most likely spin structure is a novel
"zig-zag" structure
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