Magnetic resonance pore imaging, a tool for porous media research

The internal structure of porous materials is of importance in many areas such as medicine, chemical engineering, and petrophysics. While diffraction methods such as x ray are widely used to study the internal pore space, these methods suffer from the loss of the phase information in the detected signals. Recently, an advanced diffusive diffraction NMR method was proposed [F. B. Laun et al., Phys. Rev. Lett. 107, 048102 (2011)] which is predicted to preserve the phase information, thus overcoming this severe limitation of diffraction methods in general. Here we provide experimental confirmation that the suggested approach is indeed able to acquire the diffractive signal including its phase which allows the direct image reconstruction of the pore space, averaged over all pores. We furthermore prove that this approach may combine the advantages of magnetic resonance imaging, namely, its robust and straightforward image reconstruction via a Fourier transformation with the much improved spatial resolution of pulsed gradient spin echo NMR.