Probing resonating valence bond states in artificial quantum magnets

Kai Yang, Soo-Hyon Phark, Yujeong Bae, Taner Esat, Philip Willke, Arzhang Ardavan, Andreas J. Heinrich, Christopher P. Lutz
2021 Nature Communications  
AbstractDesigning and characterizing the many-body behaviors of quantum materials represents a prominent challenge for understanding strongly correlated physics and quantum information processing. We constructed artificial quantum magnets on a surface by using spin-1/2 atoms in a scanning tunneling microscope (STM). These coupled spins feature strong quantum fluctuations due to antiferromagnetic exchange interactions between neighboring atoms. To characterize the resulting collective magnetic
more » ... llective magnetic states and their energy levels, we performed electron spin resonance on individual atoms within each quantum magnet. This gives atomic-scale access to properties of the exotic quantum many-body states, such as a finite-size realization of a resonating valence bond state. The tunable atomic-scale magnetic field from the STM tip allows us to further characterize and engineer the quantum states. These results open a new avenue to designing and exploring quantum magnets at the atomic scale for applications in spintronics and quantum simulations.
doi:10.1038/s41467-021-21274-5 pmid:33579921 fatcat:w5e5zybrrzfsrf3ojrudwdbnsm