Altomare Fabio, Chang A M, Melloch Michael R, Hong Yuguang, Tu Charles W
Physics Department, Purdue University, West Lafayette, Indiana 47906, USA.
Phys Rev Lett. 2006 Jul 7;97(1):017001. doi: 10.1103/PhysRevLett.97.017001. Epub 2006 Jul 6.
Quantum phase slips have received much attention due to their relevance to superfluids in reduced dimensions and to models of cosmic string production in the early universe. Their establishment in one-dimensional superconductors has remained controversial. Here we study the nonlinear current-voltage characteristics and linear resistance in long superconducting Al wires with lateral dimensions approximately 5 nm. We find that, in a magnetic field and at temperatures well below the superconducting transition, the observed behaviors can be described by the nonclassical, macroscopic quantum tunneling of phase slips, and are inconsistent with the thermal activation of phase slips.
量子相位滑移因其与低维超流体以及早期宇宙中宇宙弦产生模型的相关性而备受关注。它们在一维超导体中的确立一直存在争议。在此，我们研究了横向尺寸约为5纳米的长超导铝线中的非线性电流 - 电压特性和线性电阻。我们发现，在磁场中且温度远低于超导转变温度时，所观察到的行为可以用相位滑移的非经典宏观量子隧穿来描述，并且与相位滑移的热激活不一致。
