Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: NMR Investigation on Honeycomb Iridate Ag$_3$LiIr$_2$O$_6$   We investigate the structural and magnetic properties of a Kitaev spin liquid
candidate material Ag$_3$LiIr$_2$O$_6$ based on $^7$Li nuclear magnetic
resonance line shape, Knight shift and spin-lattice relaxation rate $1/T_1$.
The first sample A shows signatures of magnetically ordered spins, and exhibits
one sharp $^7$Li peak with FWHM increasing significantly below 14~K.
$1/T_1^{stretch}$ of this sample displays a broad local maximum at 40~K,
followed by a very sharp peak at $T_N = 9\pm1$~K due to critical slowing down
of Ir spin fluctuations, a typical signature of magnetic long range order. In
order to shed light on the position-by-position variation of $1/T_1$ throughout
the sample, we use Inverse Laplace Transform $T_1$ analysis based on Tikhonov
regularization to deduce the density distribution function $P(1/T_1)$. We
demonstrate that $\sim 60\%$ of Ir spins are statically ordered at the NMR
measurement timescale but the rest of the sample volume remains paramagnetic
even at 4.2~K, presumably because of structural disorder induced primarily by
stacking faults. In order to further investigate the influence of structural
disorder, we compare these NMR results with those of a second sample B, which
has been shown by transmission electron microscope to have domains with
unwanted Ag inclusion at Li and Ir sites within the Ir honeycomb planes. The
sample B displays an additional NMR peak with relative intensity of $\sim
17\%$. The small Knight shift and $1/T_1$ of these defect-induced $^7$Li sites
and the enhancement of bulk susceptibility at low temperatures suggest that
these defects generate domains of only weakly magnetic Ir spins accompanied by
free spins, leading to a lack of clear signatures of long-range order. The
apparent lack of long-range order could be easily misinterpreted as evidence
for the realization of a spin liquid ground state in highly disordered Kitaev
lattice.

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The categories of this paper are: hep-th
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The categories of this paper are: econ
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The categories of this paper are: cmp-lg
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The categories of this paper are: chao-dyn
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The categories of this paper are: solv-int
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The categories of this paper are: alg-geom
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The categories of this paper are: nlin
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The categories of this paper are: astro-ph
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The categories of this paper are: q-alg
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The categories of this paper are: math
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The categories of this paper are: dg-ga
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The categories of this paper are: gr-qc
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The categories of this paper are: q-bio
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The categories of this paper are: bayes-an
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The categories of this paper are: nucl-th
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The categories of this paper are: nucl-ex