Vortex dynamics in the intrinsic Josephson junction near the quantum regime

量子态附近本征约瑟夫森结中的涡旋动力学

• 批准号: 13640353
• 负责人: MATSUDA Yuji
• 金额: $ 2.18万
• 依托单位: The University of Tokyo
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 2001
• 资助国家: 日本
• 起止时间: 2001 至 2002
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-13640353/
• 关键词: Josephson junction; Flux flow; High-Tc superconductor; Shapiro step; Quantum region; Charging effect; Superconducting gap; Bi : 2212; 高温超伝導; ジョセフソン効果; 微細加工; ジョセフソンボルテックス; マイクロ波; クーロンブロッケイド; Bi : 2212; フラックスロー; 有機超伝導

Highly anisotropic high-Tc superconductors, such as Bi : 2212, can be considered as stacks of superconducting CuO_2 layers coupled by the Josephson interaction. Several properties which have never been observed in single Josephson junctions made from conventional low-Tc materials have been found, which are associated with the multilayer structure and with the atomic thickness of the superconducting layers. In particular, the vortex phase diagram and the related electromagnetic properties of HTSC in the presence of a strong magnetic field parallel to the layers have been the subject of recent intense experimental and theoretical studies. In this project, we report the first observation of Shapiro steps in the Josephson flux flow state of Bi : 2212 stacked junctions. When the junction is irradiated at microwave frequencies in a strong parallel magnetic field, a steep increase of the current is observed in the dc current-voltage characteristics when the external microwave frequency and the Josephson frequency are harmonically related. The existence of Shapiro steps in the Josephson flux flow state is strong evidence of coherent motion of the Josephson vortex lattice through the whole thickness of the stack.

高度各向异性高-TC超导体（例如BI：2212）可以被视为由约瑟夫森相互作用耦合的超导cuo_2层的堆叠。已经发现了与多层结构以及超导层的原子厚度相关的单个约瑟夫森连接中从未观察到的几种特性。特别是，在与层平行的强磁场存在下，HTSC的涡流相图和HTSC的相关电磁特性一直是最近激烈的实验和理论研究的主题。在这个项目中，我们报告了约瑟夫森通量流量BI：2212堆叠连接处的夏皮罗步骤的第一个观察结果。当连接处在强平行磁场中的微波频率处受照射时，当外部微波频率和约瑟夫森频率和谐相关时，在DC电流 - 电压特性中观察到电流的急剧增加。约瑟夫森通量流状态中的夏皮罗步骤的存在是约瑟夫森涡流晶格在整个堆栈厚度上连贯运动的有力证据。

项目成果

Y.Matsuda, K.Kumagai: "Vortices in Unconventional Superconductors and Superfluid-Microscopic"Springer. 18 (2001)

Y.Matsuda、K.Kumagai：“非常规超导体和超流体微观中的涡流”施普林格。

K.Izawa, T.Sasaki, Y.Matsuda: "Superconducting gap structure of κ-(BEDT-TTF)_2Cu(NCS)_2 probed by"Physical Review Letters. 88. 027002-1-027002-4 (2002)

K.Izawa、T.Sasaki、Y.Matsuda：“κ-(BEDT-TTF)_2Cu(NCS)_2 的超导间隙结构”《物理评论快报》88。027002-1-027002-4 (2002)

K.Izawa et al.: "Multiple Superconducting Phases in New Heavy Fermion Superconductor PrOs_4Sb_<12>"Phys.Rev.Lett. 90. 117001 (2003)

K.Izawa 等人：“新型重费米子超导体 PrOs_4Sb_<12> 中的多个超导相”Phys.Rev.Lett。

K. Kumagai et al.: "Charged Vortices in High Temperature Superconductors Probed by NMR"Phys. Rev. B. 63. 144502 (2001)

K. Kumagai 等人：“通过 NMR 探测高温超导体中的带电涡流”Phys。

K.Izawa et al.: "Angular position of nodes in the superconducting gap of quasi-2D heavy-fermion superconductor CeCoIn_5"Phys. Rev. Lett.. 87. 057002 (2001)

K.Izawa 等人：“准二维重费米子超导体 CeCoIn_5 超导间隙中节点的角位置”Phys。