Research for Hyperfine Nuclear Magnetism of PrPba in the Antiferro-Quadrupoinr Ordered State

反铁四价有序态PrPba超精细核磁性研究

• 批准号: 17540321
• 负责人: ABE Satoshi
• 金额: $ 2.33万
• 依托单位: Kanazawa University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 2005
• 资助国家: 日本
• 起止时间: 2005 至 2007
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-17540321/
• 关键词: Quadrupole ordering; Enhanced nuclear magnetism; Nuclear magnetic ordering; Ultra low temperatures; 反強四極子秩序; 反強四重極子秩序

We have investigated the hyperfine enhanced nuclear magnetic properties of PrPb3 at the antiferro quadrupole (AFQ) ordered state at ultra low temperatures. The static magnetization and the ac susceptibility of PrPb3 single crystals in the magnetic fields up 6.21 mT parallel to [100] and [110] directions were simultaneously measured down to below 1 mK by an ac impedance bridge using a SQUID magnetometer. In the AFQ ordered state, the hyperfine enhanced nuclear magnetic susceptibility increased below 40 mK according to the Curie Weiss law, and showed a peak at 5 mK. The enhancement factor obtained from the Curie constant was 1+K=30. The peak height at 5 mK was only 10^<3> of the expected saturated nuclear magnetization. These results suggest that the hyperfine enhanced nuclear magnetic moments of <141>^Pr antiferromagnetically order below 5 mK. The ac susceptibility in the magnetic field and the static magnetization around the zero magnetic field have a different temperature dependence from the static magnetization in the magnetic field. The ac susceptibility and the static magnetization show the superconductive diamagnetism at 35.7 mK, and the critical magnetic field at zero temperature is 0.568 mT.In order to measure the magnetic susceptibility in higher magnetic fields, we have developed a new ac susceptibility measurement system without a SQUID magnetometer which is assembled from five pick up coils and a modulation coil for mutual inductance measurement, a small superconducting solenoid for applying static magnetic filed, and the magnetic shield of niobium and it-metal cylinders. Furthermore, cooperating with Metoki group in Japan Atomic Energy Agency, we have developed a nuclear adiabatic demagnetization refrigerator for a neutron diffraction measurement at sub milikelvin temperatures for the purpose of direct observation of nuclear ordered spin structures.

我们已经研究了在超低温度下抗菌四极杆（AFQ）有序状态下PRPB3的超细增强的核磁性能。使用鱿鱼磁力计，通过交流阻抗桥同时测量了与[100]和[110]方向平行于[100]和[110]方向的静态磁化和AC敏感性，并平行于[100]和[100]方向。根据Curie Weiss定律，在AFQ有序状态下，超细增强的核磁易感性升高到40 mk以下，并显示为5 MK的峰值。从居里常数获得的增强因子为1+k = 30。 5 MK处的峰高仅为预期饱和核磁化的10^<3>。这些结果表明，超细增强了<141>^pr抗磁磁性的核磁矩在5 mk以下。磁场中的AC敏感性和零磁场周围的静态磁化与磁场中的静态磁化具有不同的温度依赖性。 AC敏感性和静态磁化表明，在35.7 MK处的超导直流电磁作用，零温度下的临界磁场为0.568 mt.in，为了测量较高磁场中的磁敏感性，我们已经开发了一个新的Ac易感性测量的新型Ac易感性磁力仪，该磁力符号是从小匹配的磁力仪，该测量量很小，该磁力尺寸是匹配的coils和Modustucation coils coils us的集合，并且超导电磁阀用于施加静态磁性，以及niobium和IT金属缸的磁罩。此外，我们与日本原子能机构的Metoki集团合作，我们开发了一个核绝热灭绝冰箱，用于在亚米克尔文温度下进行中子衍射测量，目的是直接观察核秩序的自旋结构。

项目成果

Thermal Expansion Measurement of Heavy-Fermion CeRu2Si2 at Ultra Low Temperatures II

超低温重费米子 CeRu2Si2 热膨胀测量 II

• 发表时间: 2006
• 作者: 吉田潤;阿部聡;(他4名);S. Abe;目時 直人(他5名);J. Yoshida
• 通讯作者: J. Yoshida

PrMg3の核磁気秩序状態の探索

寻找 PrMg3 的核磁有序态

• 发表时间: 2007
• 作者: 吉田潤;阿部聡;(他4名)
• 通讯作者: (他4名)

Hyperfine Nuclear Magnetism of PrPb_3 in the Antiferro-Quadrupolar Ordered State

反铁四极有序态PrPb_3的超精细核磁性

• 发表时间: 2005
• 作者: S. Abe;(他5名)
• 通讯作者: (他5名)

Magnetic properties of CeRu2Si2 at small magnetic fields and ultra low temperatures

CeRu2Si2在小磁场和超低温下的磁性能

• 发表时间: 2006
• 期刊: AIP Conf. Proc(Refereed) 850
• 作者: J. Yoshida;S. Abe;D. Takahashi;K. Matsumoto;H. Suzuki
• 通讯作者: H. Suzuki

Development of the nuclear demagnetization cryostat for neutron diffraction experiments

中子衍射实验用核退磁低温恒温器的研制

• 发表时间: 2007
• 作者: 吉田潤;阿部聡;(他4名);S. Abe
• 通讯作者: S. Abe