TY - JOUR
T1 - Invariable Simultaneous Emergence of Antiferromagnetic Order and Tetragonal Deformation in CoO Nanocrystals
AU - Ishiwata, Yoichi
AU - Kawahara, Gaku
AU - Akase, Keisuke
AU - Tominaga, Taisuke
AU - Miyazaki, Hayato
AU - Ishii, Hirofumi
AU - Matsuo, Akira
AU - Kindo, Koichi
AU - Inagaki, Yuji
AU - Akashi, Kenta
AU - Kawae, Tatsuya
AU - Kida, Tetsuya
AU - Suehiro, Satoshi
AU - Nantoh, Masashi
AU - Ishibashi, Koji
N1 - Publisher Copyright:
©2024 The Physical Society of Japan.
PY - 2024/4
Y1 - 2024/4
N2 - It remains unclear why type-II antiferromagnetic order with a propagation vector along a trigonal axis and a tetragonal Jahn–Teller deformation coexist in a low-temperature phase of CoO. Nanocrystals generally have a lower magnetic transition temperature but crystal size reduction does not affect structural transition locally induced by a crystal field. On this basis, we investigated the magnetic and structural properties of CoO nanocrystals. Both transition temperatures were equally reduced in nanocrystals, which indicates that magnetic order triggers the tetragonal deformation. This observation is consistent with a model that the Jahn–Teller deformation is assisted by spin–orbit energy splitting of t2g electrons in the high-spin Co2+ ion, proposed by Kugel and Khomskii.
AB - It remains unclear why type-II antiferromagnetic order with a propagation vector along a trigonal axis and a tetragonal Jahn–Teller deformation coexist in a low-temperature phase of CoO. Nanocrystals generally have a lower magnetic transition temperature but crystal size reduction does not affect structural transition locally induced by a crystal field. On this basis, we investigated the magnetic and structural properties of CoO nanocrystals. Both transition temperatures were equally reduced in nanocrystals, which indicates that magnetic order triggers the tetragonal deformation. This observation is consistent with a model that the Jahn–Teller deformation is assisted by spin–orbit energy splitting of t2g electrons in the high-spin Co2+ ion, proposed by Kugel and Khomskii.
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U2 - 10.7566/JPSJ.93.044603
DO - 10.7566/JPSJ.93.044603
M3 - Article
AN - SCOPUS:85189347038
SN - 0031-9015
VL - 93
JO - journal of the physical society of japan
JF - journal of the physical society of japan
IS - 4
M1 - 044603
ER -