Fabrication of THz-Band Generator Utilizing High-Temperature Josephson Superlattice

利用高温约瑟夫森超晶格制造太赫兹波段发生器

• 批准号: 10555116
• 负责人: OYA Ginichiro
• 金额: $ 8万
• 依托单位: Utsunomiya University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B)
• 财政年份: 1998
• 资助国家: 日本
• 起止时间: 1998 至 1999
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-10555116/
• 关键词: high-temperature superconductor; BiィイD22ィエD2SrィイD22ィエD2CaCuィイD22ィエD2OィイD2yィエD2; single crystal; intrinsic Josephson junction; natural superlattice; flux quantum; vortex flow; high-frequency oscillation; 高温超伝導体; 酸化物高温超伝導体; フィスケ・ステップ; 発振

The purpose of this study is to fabricate a tunable GHz-THz generator working at high temperatures on an experimental basis, which utilizes natural superlattices of intrinsic Josephson junctions, which consist of superconducting CuOィイD22ィエD2 and insulating BiO/SrO layers, in layered high-temperature oxide-superconductor BiィイD22ィエD2SrィイD22ィエD2CaCuィイD22ィエD2OィイD2yィエD2 single crystals.The results obtained in this study are as follows :1. A system for operating and measuring the generator has been prepared using a refrigerator, which can cool it down to 4.2K from 300K.2. Rectangular mesas (superlattices) as generators have been fabricated on an experimental basis from the single crystals (with transition temperatures of 〜 85K), by using photolithography and ion etching.3. The mesas have shown that on their operations, the coherent motion of flux quanta (Josephson vortices) occurs at high rates of (1-5) ×10ィイD1-6ィエD1m/s in them at 4.2K, which correspond nearly to the highest phase velocity of electromagnetic waves induced in the constituent intrinsic Josephson junctions, while at 77K, it occurs at similar high rates in the mesas with less than 20 intrinsic Josephson junctions but at much lower rates in those with more junctions.4. The mesas have shown that the frequencies of oscillations, which take place due to the motion of flux quanta at the high rates in them, can be controlled to linearly with external magnetic fields, and then an oscillation of 80GHz occurs with a magnetic field of 0.16T.5. The mesas have shown that the coherent motion of electronic (hole) waves in the intrinsic Josephson junction superlattices can be excited and controlled by current pulses, so as to generate high frequency oscillations of several ten GHz-THz.

本研究的目的是在实验基础上制造一种在高温下工作的可调谐 GHz-THz 发生器，该发生器利用本征约瑟夫森结的天然超晶格，该结由超导 CuO22D2 和绝缘 BiO/SrO 层组成，位于层状高温氧化物中-超导体BiD22D2SrD22D2CaCuD22D2OD2yD2单晶。本研究获得的结果如下：1.使用制冷机制备了用于操作和测量发生器的系统，可以将其从300K冷却到4.2K。2．发电机是在实验基础上制造的通过使用光刻和离子蚀刻，单晶（转变温度约为 85K）。 3. 台面表明，在其操作中，通量量子（约瑟夫森涡旋）的相干运动以 (1-5) 的高速率发生。 ×10D1-6D1m/s 在 4.2K 下，这几乎对应于组成本征约瑟夫森结中感应的电磁波的最高相速度，而在 77K 时，在具有少于 20 个固有约瑟夫森结的台面中，它以相似的高速率发生，但在具有更多结的台面中，其发生率要低得多。 4. 台面表明，由于运动而发生的振荡频率。其内部高速率的磁通量子，可以被控制为与外部磁场成线性关系，然后在0.16T.5的磁场下发生80GHz的振荡。台面研究表明，电流脉冲可以激发和控制本征约瑟夫森结超晶格中电子（空穴）波的相干运动，从而产生数十GHz-THz的高频振荡。

项目成果

Gin-ichiro Oya: "Intrinsic Josephson effcts and vortex dynamic properties in layered high-temperature superconductors"Recent Research Developments in Applied Physics. 2. 429-452 (1999)

Gin-ichiro Oya：“层状高温超导体中的本征约瑟夫森效应和涡流动力学特性”应用物理学的最新研究进展。

Gin-ichiro Oya: "Tunneling characteristics of intrinsic Josephson junctions in (Bi_<1-x>Pb_x)_2 Sr_2CaCu_2O_y single crystals"International Journal of Modern Physics B. 13. 3718-3720 (1999)

Gin-ichiro Oya：“(Bi_<1-x>Pb_x)_2 Sr_2CaCu_2O_y 单晶中本征约瑟夫森结的隧道特性”国际现代物理学杂志 B. 13. 3718-3720 (1999)

Akinobu Irie: "Fiske and Flux-Flow Modes of the Intrinsic Josephson Junctions in Bi_2Sr_2CaCu_2O_<2y> Mesas" Applied Physics Letters. 72・17. 2159-2161 (1998)

Akinobu Irie：“Bi_2Sr_2CaCu_2O_<2y> 台面中本征约瑟夫森结的费斯克和通量流模式”应用物理快报 72・17（1998）。

Akinobu Irie: "Dynamics of Josephson vortices in intrinsic Josephson junctions in Bi_2Sr_2CaCu_2O_y single crystal mesas"European Conference on Applied Superconductivity. (1999)

Akinobu Irie：“Bi_2Sr_2CaCu_2O_y 单晶台面中固有约瑟夫森结中的约瑟夫森涡流动力学”欧洲应用超导会议。

Gin-ichiro Oya, Shinnosuke Nozawa and Akinobu Irie: "Tunneling characteristics of intrinsic Josephson junctions in (BiィイD21-xィエD2PbィイD2xィエD2)ィイD22ィエD2SrィイD22ィエD2CaCuィイD22ィエD2OィイD2yィエD2 single crystals"International Journal of Modern Physics B. Vol. 13. 37

Gin-ichiro Oya、Shinnosuke Nozawa 和 Akinobu Irie：“D22D2OD2yD2 单晶中固有约瑟夫森结的隧道特性”《国际现代物理学杂志》B. Vol. 13. 37