arXivDaily arXiv每日学术速递 周一至周五更新
北美退伍军人节(Veterans Day),12 日无更新
arXiv 1602.03170cond-mat.mes-hall
收藏

长扩散石墨烯基约瑟夫森结中的临界电流标度

Critical current scaling in long diffusive graphene-based Josephson junctions

Chung-Ting Ke, Ivan V. Borzenets, Anne W. Draelos, Francois Amet, Yuriy Bomze, Gareth Jones, Monica Craciun, Saverio Russo, Michihisa Yamamoto, Seigo Tarucha, Gleb Finkelstein

摘要:

我们提出了长扩散石墨烯基约瑟夫森结的输运测量。在CVD石墨烯的单域晶体上制造几个结,其特征在于相同的接触宽度为~9 $μ$ m,但长度从400 nm变化到1000 nm。由于载流子密度随栅极电压调谐,这些结中的临界电流跨越从几nA到大于$5μ$ A的范围,而无载流子能量ETh几乎覆盖两个数量级。在该范围的大部分上,发现临界电流和正常电阻IcRn的乘积与ETh成线性比例,如理论所预期的。然而,发现IcRn /ETh的比率为0.1-0.2:远小于长扩散SNS结的预测值~10。

英文摘要:

We present transport measurements on long diffusive graphene-based Josephson junctions. Several junctions are made on a single-domain crystal of CVD graphene and feature the same contact width of ~9$μ$m but vary in length from 400 to 1000 nm. As the carrier density is tuned with the gate voltage, the critical current in the these junctions spans a range from a few nA up to more than $5μ$A, while the Thouless energy, ETh, covers almost two orders of magnitude. Over much of this range, the product of the critical current and the normal resistance IcRn is found to scale linearly with ETh, as expected from theory. However, the ratio IcRn /ETh is found to be 0.1-0.2: much smaller than the predicted ~10 for long diffusive SNS junctions.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

↑