Markus Ternes, Christopher P. Lutz, Andreas J. Heinrich, and Wolf-Dieter Schneider
Physical Review Letters 124, 167202 (2020)
Some spins on a surface can be measured directly with the scanning tunneling microscope (STM), an effect that we utilize heavily at QNS. Other spins remain silent and cannot be measured directly. In those cases we have to detect their magnetic behavior indirectly. In this work we show that a spin on the tip of the STM can detect such a 'dark' spin. Understanding the interaction between such spins will help researchers at QNS to make more controllable spin systems in the future.