权益分类	功能权益	普通用户	{{item.name}}会员
{{category.name}}	{{benefitItem.name}}

Fabrication of Josephson junctions with nano-injectors and investigation of fractional flux quanta.

带有纳米注射器的约瑟夫森结的制造和分数通量量子的研究。

基本信息

批准号：
221478630
负责人：
Dr. Edward Goldobin
金额：
--
依托单位：
Institut für Mikro- und Nanoelektronische Systeme (IMS)
依托单位国家：
德国
项目类别：
Research Grants
财政年份：
2013
资助国家：
德国
起止时间：
2012-12-31 至 2017-12-31
项目状态：
已结题

来源：
https://gepris.dfg.de/gepris/projekt/221478630?language=en
关键词：
Fabrication Josephson junctions nano injectors

项目摘要

Artificial phase discontinuities allow to create Josephson vortices carrying a magnetic flux, whichis an arbitrary fraction of a single flux quantum. Few experiments with these fractional Josephsonvortices were already reported by our and other groups. However, vortices created by artificialphase discontinuities are rather large in size and investigation of multi-vortex systems such asvortex molecules or 1D crystals was not possible up to now. A limiting factor is the width ofthe current injectors used to produce a phase discontinuity and the critical current density jc ofthe Josephson junction. By using e-beam lithography we are going to fabricate nano-injectors(ideally two injectors of the width ∼ 100 nm with a gap of ∼ 200 nm in between), and reduce theJosephson junction width down to ∼ 300 nm. This will allow to safely increase the jc to a fewkA/cm2 to decrease the vortex size ∝ 1/√jc. Using the new technology we will investigate multivortexmolecules and 1D vortex crystals in the clasical domain at temperatures T ∼ 0.3 . . . 6K.The successful implementation of this project will push forward the Nb/Al-AlOx/Nb Josephsonjunction technology into the nanometer domain and will also be useful for other applications, e.g.,in the quantum domain (higher classical-to-quantum crossover temperature due to higher jc andsmaller junction width).

人为的位相不连续允许产生携带磁通量的约瑟夫森涡旋，磁通量是单个磁通量的任意分数。我们和其他研究小组已经报道了很少有关于这些分数约瑟夫森涡旋的实验。然而，人工相不连续产生的涡旋尺寸较大，到目前为止，对涡旋分子或一维晶体等多涡旋系统的研究是不可能的。一个限制因素是用于产生相位不连续的电流注入器的宽度和约瑟夫森结的临界电流密度Jc。通过电子束光刻，我们将制造纳米注入器(理想情况下，两个注入器的宽度为∼100 nm，其间的间隙为∼200 nm)，并将约瑟夫森结的宽度降至∼300 nm。这将允许安全地将JC增加到几瓦卡/厘米2，以减小涡流尺寸∝1/√JC。利用这项新技术，我们将在温度T∼为0.3的情况下研究经典区域中的多涡分子和一维涡旋晶体。。。这一项目的成功实施将推动Nb/Al-AlOx/Nb约瑟夫森结技术进入纳米领域，并将有助于其他应用，例如在量子领域(由于更高的Jc和更小的结宽度，更高的经典到量子交叉温度)。