Quantum-assisted diamagnetic deflection of molecules

Abstract

We measure the diamagnetic deflection of anthracene and adamantane in a long-baseline matter-wave interferometer. From the nanometer-level deflection we extract the magnetic susceptibilities of the molecules which we compare with calculations and previous results. Adamantane yields an isotropic average mass susceptibility of −8.0 ± 1.1 m³ kg⁻¹, consistent with expectations, while anthracene yields a higher-than-anticipated value of −13.6 ± 1.3 m³ kg⁻¹. We attribute the high anthracene value to the planar aromatic molecule's magnetic anisotropy and partial alignment in the molecular beam, and estimate the magnitude of the effect on the observed deflection.