Nuclear spin structure of Sc metal-tvi ansle lattice spin structure-

Sc金属的核自旋结构-tvi ansle晶格自旋结构-

• 批准号: 08454094
• 负责人: SUZUKI Haruhiko
• 金额: $ 4.48万
• 依托单位: Kanazawa University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B)
• 财政年份: 1996
• 资助国家: 日本
• 起止时间: 1996 至 1997
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-08454094/
• 关键词: Ultra Low Temperature; Nuclear Magnetism; NMR; Relaxation Time; SQUZD; Nuclear Demagnetization; 核断熱消磁冷却; スピン格子緩和時間; SQUZD

1) To determine the nuclear spin structure, we measured the spin-lattice relaxation time which gives the information about the RK-interaction between the nuclear spins. As the nuclear spin of Sc metal is I=7/2 and the crystal structure is hcp, nuclear spin levels split into 4 doublets due to the electric quadrupole interaction. This quadrupole splitting makes it so hard to measure the spin-lattice relaxation time by pulse NMR method. We succeeded to measure the NMR for a single crystal of Sc. We obtained the Korringa constant _K(T_1T) =1.20sec・K for c-axis and 1.0sec・K for a-axis. We sill measure the T1 at lower temperatures and also the magnetic field dependence of T1.2) To achieve the nuclear spin order of Sc in Kanazawa university, we constructed the nuclear demagnetization cryostats. We succeeded to get 200muK and we measured the magnetic susceptibility of the heavy electron compund CeRu2Si2 down to less than 300muK.contradicted to the previous report, the magnetic susceptibility increases with decreasing temperature monotonically and does not show any anomaly down to 300muK.

1)为了确定核自旋结构，我们测量了自旋-晶格弛豫时间，它给出了关于核自旋之间的RK相互作用的信息。由于Sc金属的核自旋为I=7/2，晶体结构为hcp，由于电四极相互作用，核自旋能级分裂为4个二重态。这种四极分裂使得用脉冲核磁共振方法测量自旋-晶格弛豫时间变得困难。我们成功地测量了Sc单晶的核磁共振谱，得到了c轴和a轴的柯林加常数K（T_1T）分别为1.20秒·K和1.0秒·K。2）在金泽大学为了获得Sc的核自旋有序，我们建造了核退磁低温恒温器。我们成功地得到了200 μ K，我们测量的磁化率的重电子化合物CeRu_2Si_2下降到小于300 μ K。与以前的报告相矛盾，磁化率随着温度的降低单调增加，并没有显示出任何异常下降到300 μ K。

项目成果

Haruhiko, Suzuki: "Nuclear spin order of scandium" Czeck,J.of Physics. 46.SupplS4. 2183-2184 (1996)

Haruhiko, Suzuki：“钪的核自旋顺序” Czeck，J.of 物理学。

Y.Koike and H.Suzuki: "Magnetic Susceptibility of Sc Single Crystal" J.Low Temp.Phys. vol 107. 197-208 (1997)

Y.Koike 和 H.Suzuki：“Sc 单晶的磁化率”J.Low Temp.Phys。

H.Suzuki, Y.Koike, K.Karaki, M.Kubota and H.Ishimoto: "Nuclear Spin order of scandium." Czech, J.Phys. S4. 2183-2184 (1996)

H.Suzuki、Y.Koike、K.Karaki、M.Kubota 和 H.Ishimoto：“钪的核自旋顺序”。

Haruhiko Suzuki: "Nuclear spin order of scandium" Czeck.J.of Physics. 46.suppl S4. 2183-2184 (1996)

Haruhiko Suzuki：“钪的核自旋顺序”Czeck.J.of 物理学。

Zen-ichi, Iida: "Magnetic Susceptibility of nonmagnetic CeRu_2Si_2 below 1mK" Czeck,J.of Physics. 46.S5. 2579-258? (1996)

Zen-ichi, Iida：“非磁性 CeRu_2Si_2 的磁化率低于 1mK” Czeck，J.of 物理学。