Distinguishing dual lattice by strong-pulse matter-wave diffraction

TL;DR

This paper demonstrates that strong-pulse matter-wave diffraction can distinguish dual optical lattices like honeycomb and hexagonal, breaking Babinet's principle and enabling precise lattice characterization beyond traditional optical methods.

Contribution

It introduces a phase wrapping method to break Babinet's principle in strong-pulse Kapitza--Dirac diffraction, allowing clear differentiation of dual lattices.

Findings

Strong-pulse diffraction breaks Babinet's principle.

Distinct interference patterns for honeycomb and hexagonal lattices.

Enhanced precision in lattice configuration characterization.

Abstract

Dual lattices such as honeycomb and hexagonal lattices typically obey Babinet's principle in optics, which states that the expected interference patterns of two complementary diffracting objects are identical and indistinguishable, except for their overall intensity. Here, we study Kapitza--Dirac diffraction of Bose--Einstein condensates in optical lattices and find that matter waves in dual lattices obey Babinet's principle only under the condition of weak-pulse Raman--Nath regimes. In contrast, the Kapitza--Dirac matter-wave diffraction in the strong-pulse Raman--Nath regime (corresponding to the phase wrapping method we developed to generate sub-wavelength phase structures in Sci. Rep. 10, 5870 (2020)) can break Babinet's principle and clearly resolve the distinct interference patterns of the dual honeycomb and hexagonal lattices. This method offers exceptional precision in characterizing lattice configurations and advance the study of symmetry-related phenomena, overcoming the limitations of real-space imaging.