Towards force detected single electron spin resonance at room temperature

Electrically detected magnetic resonance (EDMR) spectroscopy has shown that electron tunneling at or within silicon dioxide layers is strongly dependent on spin-selection rules [1]. Also demonstrated is the detection of single electron tunneling events by electrostatic force with sub-nanometer spatial resolution [2,3]. Here we propose to combine force detected single electron tunneling microscopy with EDMR to demonstrate a new kind of single spin force microscope. This approach has much better sensitivity than magnetic force based single spin microscopes [4], since electrostatic forces are much larger than corresponding magnetic forces. In this method, a paramagnetic state in an oxidized AFM probe tip is brought within tunneling range of a paramagnetic state in an oxide surface [5]. Under appropriate energy conditions, one of the unpaired electrons can randomly tunnel between the two states causing a random telegraph signal (RTS) to appear on the AFM cantilever frequency. Simulations predict that if magnetic resonance conditions are achieved, a measurable change in the RTS signal is detectable at room temperature. The theory and a quantitative simulation of this atomic scale spin resonance measurement will be presented, along with experimentally observed random telegraph signals.\\[4pt] [1] D. R. McCamey, et al., \textit{Phys. Rev. B}, \textbf{78}, 045302 (2008). [2] L. J. Klein and C.C. Williams, \textit{Appl. Phys. Lett.}\textbf{ 79}, 1828 (2001). [3] E. Bussmann and D.J. Kim, and C.C. Williams, \textit{Appl. Phys. Lett.} \textbf{85}, 2538 (2004). [4] D. Rugar et al., \textit{Nature} \textbf{430}, 329 (2004). [5] J.P. Johnson, Ph.D. Thesis, Dept. of Physics, University of Utah (2010).