Electron Spin Relaxation Near a Micron-Size Ferromagnet

B. C. Stipe; H. J. Mamin; C. S. Yannoni; T. D. Stowe; T. W. Kenny; D. Rugar

doi:10.1103/PhysRevLett.87.277602

Electron Spin Relaxation Near a Micron-Size Ferromagnet

B. C. Stipe, H. J. Mamin, C. S. Yannoni, T. D. Stowe, T. W. Kenny, and D. Rugar

Phys. Rev. Lett. 87, 277602 – Published 13 December 2001

Abstract

Magnetic resonance force microscopy was used to study the behavior of small ensembles of unpaired electron spins in silica near a micrometer-size ferromagnetic tip. Using a cantilever-driven spin manipulation protocol and a magnetic field gradient greater than $10^{5} T / m$ , signals from as few as 100 net spins within a 20 nm thick resonant slice could be studied. A sixfold increase in the spin-lattice relaxation rate was found within 800 nm of the ferromagnet, while no effect due to silica surface proximity was detected. The results are interpreted in terms of Larmor-frequency magnetic field fluctuations emanating from the ferromagnet.

Received 31 August 2001

DOI:https://doi.org/10.1103/PhysRevLett.87.277602

Authors & Affiliations

B. C. Stipe¹, H. J. Mamin¹, C. S. Yannoni¹, T. D. Stowe², T. W. Kenny³, and D. Rugar¹

¹IBM Research Division, Almaden Research Center, 650 Harry Road, San Jose, California 95120
²Department of Applied Physics, Stanford University, Stanford, California 94305
³Department of Mechanical Engineering, Stanford University, Stanford, California 94305