5 research outputs found
Relaxometry and Dephasing Imaging of Superparamagnetic Magnetite Nanoparticles Using a Single Qubit
To study the magnetic dynamics of
superparamagnetic nanoparticles, we use scanning probe relaxometry
and dephasing of the nitrogen vacancy (NV) center in diamond, characterizing
the spin noise of a single 10 nm magnetite particle. Additionally,
we show the anisotropy of the NV sensitivity’s dependence on
the applied decoherence measurement method. By comparing the change
in relaxation (<i>T</i><sub>1</sub>) and dephasing (<i>T</i><sub>2</sub>) time in the NV center when scanning a nanoparticle
over it, we are able to extract the nanoparticle’s diameter
and distance from the NV center using an Ornstein–Uhlenbeck
model for the nanoparticle’s fluctuations. This scanning probe
technique can be used in the future to characterize different spin
label substitutes for both medical applications and basic magnetic
nanoparticle behavior