2026-08-21 中国科学院（CAS）
＜関連情報＞
- https://english.cas.cn/newsroom/research-news/202608/t20260819_1188615.shtml
- https://www.nature.com/articles/s41586-026-11037-x
- https://www.nature.com/articles/s41567-024-02521-0
NbSe₂における真空増強超伝導の証拠 Evidence for vacuum-enhanced superconductivity in NbSe2
Zheyan Wang,Gabriel Cardoso,Liu Yang,Xun Gong,Chi Zhang,Yufei Zhu,Dongbo Zhang,Nan Pan,Hongbing Cai,Yong P. Chen,Qing-Dong Jiang,Guanghui Cheng,Frank Wilczek & Changgan Zeng
Nature Published:19 August 2026
DOI:https://doi.org/10.1038/s41586-026-11037-x Early provide
Abstract
Vacuum fluctuations provide an important new way to control material properties noninvasively1-6. Here, we present experimental evidence that they can enhance superconductivity. NbSe2 is a layered transition-metal dichalcogenide with well-characterized superconducting behavior, providing a clear platform to reveal this effect. We have observed an increase in the critical temperature of superconducting NbSe2 when it is embedded in a split-ring cavity resonator. Near the transition temperature, the critical current and critical field increase dramatically. Our observations are consistent with theoretical calculations showing that hybridization between electronic degrees of freedom and fluctuating cavity modes lowers the energy of the superconducting state. By providing a proof-of-principle demonstration of superconductivity enhancement via vacuum fluctuations, our work establishes a noninvasive technique for controlling the mainstay of quantum technology.
カシミール力の磁場による調整 Magnetic-field tuning of the Casimir force
Yichi Zhang,Hui Zhang,Xiuxia Wang,Yiheng Wang,Yuchen Liu,Shu Li,Tianyi Zhang,Chuang Fan &Changgan Zeng
Nature Physics Published:24 May 2024
DOI:https://doi.org/10.1038/s41567-024-02521-0
Abstract
The quantum fluctuation-induced Casimir force can be either attractive or repulsive, depending on the dielectric permittivities and magnetic permeabilities of the materials involved. However, it is challenging to manipulate the dielectric permittivities of most materials using external fields. In contrast, the magnetic permeabilities of ferrofluids can be readily tuned by magnetic fields, which opens up the possibility of magnetic-field tuning of the Casimir force. Here, we demonstrate that this tuning can be achieved for a gold sphere and a silica plate immersed in water-based ferrofluids. Our theoretical calculations predict that, by varying the magnetic field, separation distance and ferrofluid volume fraction, the Casimir force can be tuned from attractive to repulsive over a wide range of parameters in this system. Experimentally, we develop a cantilever designed to conduct measurements within water-based ferrofluids. Using this setup, we observe the predicted transitions. These findings may lead to the development of switchable micromechanical devices based on the Casimir effect.
