The desire to probe and control individual quantum systems has driven significant scientific and engineering advances in quantum coherent nanoscience. Meanwhile, single atoms and molecules on surfaces have been extensively studied in search of novel electronic and magnetic functionalities. These two paths came together in 2015 when it was clearly demonstrated that individual spins on surfaces can be coherently controlled and read out in an all-electrical fashion [1]. The enabling technique is scanning tunneling microscopy (STM) combined with electron spin resonance (ESR) [2], which provides unprecedented coherent control over quantum states at the Angstrom length scale.
Using ESR-STM, we demonstrated the coherent manipulation of not only individual spins but also multiple electron spins in artificially built spin structures on surfaces [3]. In these systems, we found that remote spins, which are positioned outside the tunnel junction, can be controlled by local oscillating magnetic fields created by a single-atom magnet placed next to them in oscillating electric fields. Read-out of multiple spins is achieved by a sensor atom weakly coupled to them. While traditional STM studies have focused on spins located at the STM junction, our approach extends STM’s capability to harness multiple spins in coherent manner. Furthermore, we recently succeeded in functionalizing the STM tip with spin-polarized magnetic atoms and a molecule containing an ESR-active spin center. This allows the tip to act as a mobile ESR sensor, facilitating the precise detection of the electric and magnetic fields at the atomic level [4]. Our work widens the approaches for tailoring spin structures on surfaces with atomic precision in the realm of the quantum information science and quantum sensing.
References
[1] S. Baumann et al., Science 350, 417 (2015) 417.
[2] Y. Chen et al., Adv. Mater. 35, 2107534 (2022).
[3] Y. Wang et al., Science 382, 87 (2023).
[4] T. Esat et al., Nat. Nano. 19, 1466 (2024).
Location: Stuckelberg, Ecole de Physique
Time: Friday 22 May 2026, 12:30 for pizza, 13:00 start discussion
Friday 22 May 2026
Atomic-Scale Quantum Science with Spins on Surfaces
Yujeong Bae (Empa – Swiss Federal Laboratories for Materials Science and Technology)
by Dmitry | May 12, 2026 | Next Meeting