Field Induced Lattice Deformation in a Quasi-One-Dimensional Antiferromagnet BaCo2V2O8

被引：5

作者：

Kimura, Shojiro ^{[1
]}

Narumi, Yasuo ^{[2
]}

Terada, Noriki ^{[3
]}

Tanaka, Yoshikazu ^{[4
]}

Iwaki, Masahiro ^{[5
]}

Katsumata, Koichi ^{[4
]}

Hagiwara, Masayuki ^{[1
]}

Kindo, Koichi ^{[5
]}

He, Zhangzhen ^{[6
]}

Taniyama, Tomoyasu ^{[8
]}

Itoh, Mitsuru ^{[8
]}

Toyokawa, Hidenori ^{[7
]}

Ishikawa, Tetsuya ^{[4
]}

Kitamura, Hideo ^{[4
]}

机构：

[1] Osaka Univ, KYOKUGEN, Osaka 5608531, Japan

[2] Tohoku Univ, Inst Mat Res, Sendai, Miyagi 9808577, Japan

[3] Natl Inst Mat Sci, Tsukuba, Ibaraki 3050044, Japan

[4] Harima Inst, RIKEN SPring Ctr 8, Sayo, Hyogo 6795148, Japan

[5] Univ Tokyo, ISSP, Chiba 2778581, Japan

[6] Chinese Acad Sci, Fujian Inst Res Struct Matter, Fuzhou 350002, Fujian, Peoples R China

[7] SPring 8 JASRI, Sayo, Hyogo 6795198, Japan

[8] Tokyo Inst Technol, Mat & Struct Lab, Yokohama, Kanagawa 2268503, Japan

来源：

JOURNAL OF THE PHYSICAL SOCIETY OF JAPAN | 2010年 / 79卷 / 04期

基金：

日本学术振兴会;

关键词：

BaCo2V2O8; quasi-one-dimensional antiferromagnet; synchrotron X-ray diffraction; high magnetic field; magneto-elastic coupling; exchange interaction;

D O I：

10.1143/JPSJ.79.043706

中图分类号：

O4 [物理学];

学科分类号：

0702 ;

摘要：

Synchrotron X-ray diffraction is used to study the correlation between crystal structure and magnetism in a quasi-one-dimensional uniaxial antiferromagnet BaCo2V2O8. When an external magnetic field, B, is applied parallel to the c-axis in the short-range-ordered phase, the lattice constant, a elongates, while c shrinks with increasing B. We calculate the exchange energy under applied magnetic fields based on the proposed magnetic structure. We are successful in explaining the contrasting behavior of the lattice deformations. Our calculation shows that the change in the lattice constants is proportional to M-2, where M is the magnetization. A good agreement between theory and experiment is obtained for the a-axis up to the saturation field, B-s. Above B-s, an M-4 term is necessary, in addition to the M-2 one, to obtain a better agreement. For the c-axis, a sum of the M-2 and M-4 terms gives a reasonable fit to the experimental data.

引用

页数：4

共 24 条

[1] AN APPROXIMATE QUANTUM THEORY OF THE ANTIFERROMAGNETIC GROUND STATE [J].