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SbO
Piyakulworawat, C.*; Morita, Katsuhiro*; Fukumoto, Yoshiyuki*; Hsieh, W.-Y.*; Chen, W.-T.*; Nakajima, Kenji; Kawamura, Seiko; Zhao, Y.*; Wannapaiboon, S.*; Piyawongwatthana, P.; et al.
Physical Review Research (Internet), 8(1), p.013247_1 - 013247_16, 2026/03
We analyze powder-averaged inelastic neutron scattering and magnetization data for the distorted honeycomb compound Cu
SbO
using a first-order dimer expansion calculation and quantum Monte Carlo simulations. We show that, in contrast to the previously proposed honeycomb lattice model, Cu
SbO
accommodates interacting dimerized spin chains with alternating ferromagnetic-antiferromagnetic couplings along the chain. Moreover, unlike the typical couplings observed in other Cu
-based distorted honeycomb magnets, the spin chains in Cu
SbO
primarily couple through an antiferromagnetic coupling that arises between the honeycomb layers, rather than the expected interchain coupling in the layers. This finding reveals a different magnetic coupling scheme for Cu
SbO
. In addition, utilizing X-ray spectroscopy and transmission electron microscopy, we also refine the crystal structure and stacking-fault model of the compound.

H
OFujihara, Masayoshi; Hagihara, Masato; Morita, Katsuhiro*; Murai, Naoki; Koda, Akihiro*; Okabe, Hirotaka*; Mitsuda, Setsuo*
Physical Review B, 107(5), p.054435_1 - 054435_8, 2023/02
Times Cited Count:5 Percentile:34.19(Materials Science, Multidisciplinary)The
= 1/2 Heisenberg linear chain antiferromagnet is the simplest spin model; nevertheless it serves as a platform for various quantum many-body phenomena. Here, we report the magnetic behavior of a quasi-one-dimensional antiferromagnet KCuPO
H
O. A long-range commensurate antiferromagnetic order with ordered moment 0.31(1)
per spin occurs at
= 11.7(1) K. Above
, the inelastic neutron excitation is characterized by a two spinon continuum. The intrachain interaction
and interchain interaction
are estimated to be 172 K and 4.25(4) K, respectively; thus the ratio of the
/
= 0.0247(3). At lower energies, below
, a spin gap is observed in the dispersive excitations. These results are consistent with characteristics observed in weakly interacting
= 1/2 Heisenberg chain system.
Cu
(PO
)
SO
5H
O as a model antiferromagnetic spin-1/2 Heisenberg 
-
chainFujihara, Masayoshi; Jeschke, H. O.*; Morita, Katsuhiro*; Kuwai, Tomohiko*; Koda, Akihiro*; Okabe, Hirotaka*; Matsuo, Akira*; Kindo, Koichi*; Mitsuda, Setsuo*
Physical Review Materials (Internet), 6(11), p.114408_1 - 114408_8, 2022/11
Times Cited Count:6 Percentile:26.77(Materials Science, Multidisciplinary)
= 1/2 Heisenberg 
-
chain antiferromagnets have been investigated extensively due to their exotic magnetic states. Here, we report the magnetic behavior of birchite Cd
Cu
(PO
)
SO
5H
O and its effective spin model. Experimental studies by magnetic susceptibility, magnetization, heat capacity, and
SR measurements indicate the absence of long-range order down to 0.4 K. Theoretical studies reveal that birchite is a model compound for the 
-
antiferromagnetic chain: the intrachain interactions 
and 
are antiferromagnetic and their magnitude is about 100 times larger than the interchain interactions. The magnitude of 
is two to three times larger than that of 
, thus the spin gap is expected to be only a few percent of that of 
. The temperature dependence of the specific heat shows a broad peak at about 1 K (
0.036 
), which suggests the presence of a spin gap.
Fujihara, Masayoshi*; Morita, Katsuhiro*; Mole, R.*; Mitsuda, Setsuo*; Toyama, Takami*; Yano, Shinichiro*; Yu, D.*; Sota, Shigetoshi*; Kuwai, Tomohiko*; Koda, Akihiro*; et al.
Nature Communications (Internet), 11, p.3429_1 - 3429_7, 2020/07
Times Cited Count:70 Percentile:93.21(Multidisciplinary Sciences)
H
OFujihara, Masayoshi; Morita, Katsuhiro*; Mitsuda, Setsuo*; Okabe, Hirotaka*; Koda, Akihiro*; Murai, Naoki; Hagihara, Masato
no journal, ,
no abstracts in English