RF-Field-Driven Superconducting Quantum Interference Devices

射频场驱动超导量子干涉装置

• 批准号: 12450135
• 负责人: YAMASHITA Tsutomu
• 金额: $ 9.28万
• 依托单位: Tohoku University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B)
• 财政年份: 2000
• 资助国家: 日本
• 起止时间: 2000 至 2001
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-12450135/
• 关键词: radio-frequency; field-driven; SQUID; Josephson junction; zero-crossing steps; voltagestandards; flux quantum; 磁束量子; 粒界ジョセフソン接合; コプレーナ型共振器; スイッチング素子; A; D変換器; バイクリスタル基板; YBCO薄膜

The purpose of this study is to investigate the properties of RF-field-driven DC-SQUID (RFDS) in both simulation and experiments for future possible applications. In simulation, we have obtained the dependence of device properties upon (i) frequency of the signal, (ii) power of the signal, (iii) offset DC field, and (iv) operation margins and power gain. Next we fabricated a DC-SQUID using YBa_2Cu_3O_<7-δ> grain boundary Josephson junctions (YBCO-GBJJs) integrated with an H-shaped antenna. The results agreed with numerical ones at low power region. According to these results, we developed a coplanar-type resonator to apply RF signal to a superconducting quantum interference device (SQUID) magnetically. We fabricated a DC-SQUID using YBCO-GBJJs again, and mounted it on the resonator. By applying SF signal of 20GHz to the resonator, we observed Shapiro steps on ;the current-voltage characteristics of the SQUID. The dependence of Shapiro steps upon DC offset field agreed with the numerical results. In comparison with our previous device, the new method has three benefits: 1. We can design a resonator and a SQUID independently. 2. Hence, we can utilize wide-band frequencies by changing the resonator. 3. Also we can utilize the same SQUID for wide-band frequencies, which means we can systematically investigate the dependence of the device properties upon the frequency. Finally we extended the device configuration from two-junction SQUID to three-junction SQUID. Analytical and numerical results showed that the three-junction SQUID would generate a zero-crossing Shapiro step by applying multi-phase RF signals. Hence, the extended RF-Field-Driven SQUID would be applicable to programmable Josephson voltage standards.

本研究的目的是研究射频场驱动的 DC-SQUID (RFDS) 在模拟和实验中的特性，以供未来可能的应用。在仿真中，我们获得了器件特性对 (i) 信号频率、(ii) 信号功率、(iii) 偏置直流场以及 (iv) 操作裕度和功率增益的依赖性。接下来，我们使用与 H 形天线集成的 YBa_2Cu_3O_<7-δ> 晶界约瑟夫森结 (YBCO-GBJJs) 制造了 DC-SQUID。结果与低功率区域的数值结果一致。根据这些结果，我们开发了一种共面型谐振器，以磁性方式将射频信号施加到超导量子干涉装置（SQUID）。我们再次使用 YBCO-GBJJ 制作了 DC-SQUID，并将其安装在谐振器上。通过将20GHz的SF信号施加到谐振器，我们观察了Shapiro步进SQUID的电流-电压特性。夏皮罗阶跃对直流偏移场的依赖性与数值结果一致。与我们以前的设备相比，新方法具有三个优点： 1.我们可以独立设计谐振器和SQUID。 2. 因此，我们可以通过改变谐振器来利用宽带频率。 3. 我们还可以将相同的 SQUID 用于宽带频率，这意味着我们可以系统地研究器件特性对频率的依赖性。最后，我们将器件配置从两结 SQUID 扩展到三结 SQUID。分析和数值结果表明，三结 SQUID 将通过应用多相射频信号产生过零夏皮罗阶跃。因此，扩展的射频场驱动 SQUID 将适用于可编程约瑟夫森电压标准。

项目成果

Y. Mizugaki, J. Chen, K. Nakajima, and T. Yamashita: ""Flux-Quantum Transitions in a Three-Junction SQUID Controlled by Two RF Signals""IEICE Transactions on Electronics. vol. E85-C(to be published). (2002)

Y. Mizugaki、J. Chen、K. Nakajima 和 T. Yamashita：““由两个 RF 信号控制的三结 SQUID 中的通量量子跃迁””IEICE Transactions on Electronics。

Y.Mizugaki, J.Chen, K.Nakajima, T.Tamashita: "Flux-Quantum Transitions in a Three-Junction SQUID Controlled by Two RF Signals"IEICE Transactions on Electronics. E85-C・3(発表予定). (2002)

Y.Mizugaki、J.Chen、K.Nakajima、T.Tamashita：“由两个 RF 信号控制的三结 SQUID 中的通量量子跃迁”IEICE Transactions on Electronics（即将公布）。 2002年）

T. Kondo, Y. Mizugaki, K, Saito, K. Nakajima, and T. Yamashita: ""Switching Device Based on RF-Field-Driven High-Tc SQUID""IEICE Transactions on Electronics. vol. E-84C. 55-60 (2001)

T. Kondo、Y. Mizugaki、K、Saito、K. Nakajima 和 T. Yamashita：“基于 RF 场驱动的高温 SQUID 的开关器件”“IEICE Transactions on Electronics。

H.B.Wang,Y.Aruga,J.Chen,K.Nakajima,T.Yamashita,and P.H.Wu: "Individual Shapiro steps observed in resistively-shunted intrinsic Josephson junctions on Bi_2Sr_2CaCu_2O_<8+x> single crystal"Appl.Phys.Lett.. 77・7. 1017-1019 (2000)

H.B.Wang、Y.Aruga、J.Chen、K.Nakajima、T.Yamashita 和 P.H.Wu：“在 Bi_2Sr_2CaCu_2O_<8+x> 单晶上的电阻分流本征约瑟夫森结中观察到的单独夏皮罗阶跃”Appl.Phys.Lett .. 77・7. 1017-1019 (2000)

T. Kondo, Y. Mizugaki, J. Chen, K. Nakajima, and T. Yamashita: ""Microwave Induced Steps in RF-Field-Driven DC SQUID and its Potential Applications""IEEE Transactions on Applied Superconductivity. vol. 11. 900-903 (2001)

T. Kondo、Y. Mizugaki、J. Chen、K. Nakajima 和 T. Yamashita：“射频场驱动 DC SQUID 中的微波感应阶跃及其潜在应用””IEEE 应用超导汇刊。