Theory and experimental verification of Kapitza-Dirac-Talbot-Lau interferometry

TL;DR

This paper presents a comprehensive theoretical model and experimental validation of Kapitza-Dirac-Talbot-Lau interferometry, demonstrating quantum wave behavior in large molecules with high precision across various molecular parameters.

Contribution

It introduces a phase space model for KDTLI that accounts for molecular phase shifts and photon absorption, validated by experiments with fullerenes and fluorofullerenes.

Findings

High-precision agreement between theory and experiments with C60, C70, C60F36, and C60F48 molecules.

Model accurately predicts interference patterns considering optical dipole and absorption effects.

Experimental results confirm the quantum wave nature of large molecules in KDTLI setup.

Abstract

Kapitza-Dirac-Talbot-Lau interferometry (KDTLI) has recently been established for demonstrating the quantum wave nature of large molecules. A phase space treatment permits us to derive closed equations for the near-field interference pattern, as well as for the Moire-type pattern that would arise if the molecules were to be treated as classical particles. The model provides a simple and elegant way to account for the molecular phase shifts related to the optical dipole potential as well as for the incoherent effect of photon absorption at the second grating. We present experimental results for different molecular masses, polarizabilities and absorption cross sections using fullerenes and fluorofullerenes and discuss the alignment requirements. Our results with C60 and C70, C60F36 and C60F48 verify the theoretical description to a high degree of precision.