Press Releases

DATE2023.09.16 #Press Releases

UTokyo researchers successfully imaged quantum vortices in superconductors

Using a diamond quantum sensor, researchers could quantify the magnetic field of many quantum vortices with high accuracy. 
Sep 16, 2023  
When a superconductor is exposed to magnetic fields, circulating loops of currents called quantum vortices form around the quantized magnetic flux. Understanding quantum vortices is helpful for the fundamentals of superconductivity and the development of superconductors. Although various methods exist to visualize quantum vortices, it has been challenging to observe many vortices quantitatively and simultaneously.  
Shinsuke Nishimura and colleagues from the University of Tokyo have now succeeded in visualizing the superconductor quantum vortices using a perfectly aligned diamond quantum sensor. This new method advances superconducting material research, as it enables quantitative investigation of the magnetic field of many quantum vortices in superconductors. 
The team imaged quantum vortices in thin superconducting films (of YBa2Cu3O7−δ; YBCO) at various temperatures and magnetic fields. They confirmed the accuracy of the technique based on the consistency with theoretical models and known temperature dependence of the vortex shape. Thus, the wide-field imaging method they developed will have broad applications in the superconductor research field. 

Figure: Magnetic field imaging of the quantum vortices in YBCO at 40 K. 
For more details, please read the article:   
Shunsuke Nishimura, Taku Kobayashi, Daichi Sasaki, Takeyuki Tsuji, Takayuki Iwasaki, Mutsuko Hatano, Kento Sasaki, and Kensuke Kobayashi. 2023. Wide-field quantitative magnetic imaging of superconducting vortices using perfectly aligned quantum sensors. Applied Physics Letters. DOI:10.1063/5.0169521