Martino Poggio

Title

Magnetic Resonance Imaging with Nanomechanics

Abstract

Can we use the same forces that cause two magnets to attract or repel each other to measure the dynamics of single spins? This is the basic question driving research in mechanically detected magnetic resonance. In conventional magnetic resonance, the dynamics of a spin ensemble alter magnetic fields inside a pick-up coil inducing currents in that coil. While this works beautifully for macroscopic samples, the scheme breaks down, as samples approach the nanoscale. Moving to a mechanicallydetected technique is one solution to this problem. In such methods, the oscillating force between spins and a small magnet drive a compliant cantilever. The cantilever's mechanical oscillations are then measured using an optical interferometer. I will describe how mechanically detected techniques have been used to do nanoscale magnetic resonance imaging, achieving a billion-fold improvement in the volume sensitivity over inductively-detected methods. Could a "molecular structure microscope", whereby one could image the atomic structure of macromolecules, be around the corner?