Magnetic Properties of Fe$_{\mathrm{3}}$O$_{\mathrm{4\thinspace }}$Nanoparticle Assemblies

We are studying magnetic ordering and magnetic properties in Fe$_{\mathrm{3}}$O$_{\mathrm{4}}$ nanoparticles assemblies. These particles have a variety of applications, including: drug targeting, cancer therapy and MRI applications. We have recently (in February 2015) performed a synchrotron experiment at SLAC at Stanford, to measure the X-ray magnetic circular dichroism (XMCD) and the X-ray Resonant Magnetic Scattering (XRMS) signal of nanoparticles we freshly prepared. We use the XMCD signal to extract the spin and orbital magnetic moments in Fe$_{\mathrm{3}}$O$_{\mathrm{4}}$. In addition, we use the XRMS patterns to extract a magnetic profile that provides information about the magnetic order in the nanoparticle assembly and its dependency on particle size and concentration.