Magnetotransport Experiments on Fully Metallic Superconducting Dayem-Bridge Field-Effect Transistors
Magnetotransport Experiments on Fully Metallic Superconducting Dayem-Bridge Field-Effect Transistors
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DOI：
10.1103/physrevapplied.11.024061
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发表时间：
2019-02-25
影响因子：
4.6
通讯作者：
Giazotto, Francesco
中科院分区：
文献类型：
--
作者：
Paolucci, Federico;De Simoni, Giorgio;Giazotto, Francesco
在过去的60年中，传统的固体和电解质门控允许在金属超导体中的表面载流子浓度的相当大的调制，导致其电导率的调谐和其临界温度的变化。最近在超导金属纳米结构上进行的常规门控实验表明，在不改变正常态电阻和临界温度的情况下，临界电流得到了完全抑制。这些结果仍然缺乏微观解释。在这篇文章中，我们描述了一套完整的门控实验钛基超导Dayem桥和建议的经典热力学模型，似乎占我们的几个实验结果。特别是，零偏置电阻和临界电流的I-C测量突出了以下几点：抑制I-C与栅极电压的两个极性，表面性质的效果，从电场的临界温度的独立性，和栅极诱导生长的subgap耗散组件。此外，约瑟夫森临界电流的温度依赖性似乎表现出从弹道Kulik-Omelyanchuk行为的Ambegaokar-Baratoff隧道行为的电场的增加。此外，I-C抑制持续存在于相当大的平行于平面的磁场中。我们提出了一个经典的热力学模型，能够描述一些实验观察的本和以前的工作。最重要的是，该模型抓住了双极电场诱导的抑制的I-C和出现的子间隙耗散组件附近的超电流的完全抑制。最后，应用所讨论的效果提出。
In the last 60 years conventional solid and electrolyte gating has allowed sizable modulations of the surface carrier concentration in metallic superconductors, resulting in tuning of their conductivity and change of their critical temperature. Recent conventional gating experiments on superconducting metal nanostructures showed full suppression of the critical current without variation of the normal-state resistance and the critical temperature. These results still lack a microscopic explanation. In this article, we describe a complete set of gating experiments on Ti-based superconducting Dayem-bridges and a proposed classical thermodynamic model that seems to account for several of our experimental findings. In particular, zero-bias resistance and critical-current I-C measurements highlight the following: the suppression of I-C with both polarities of gate voltage, the surface nature of the effect, the independence of critical temperature from the electric field, and the gate-induced growth of a subgap dissipative component. In addition, the temperature dependence of the Josephson critical current seems to show a transition from ballistic Kulik-Omelyanchuk behavior to Ambegaokar-Baratoff tunnellike behavior on increase of the electric field. Furthermore, the I-C suppression persists in the presence of sizable perpendicular-to-plane magnetic fields. We propose a classical thermodynamic model able to describe some of the experimental observations of the present and previous work. Above all, the model grabs the bipolar-electric-field-induced suppression of I-C and the emergence of a subgap dissipative component near full suppression of the supercurrent. Finally, applications using the effect discussed are proposed.