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DOE OSTI · 2879155

Strategy for Direct Detection of Chiral Phonons with Phase-Structured Free Electrons

Bourgeois, Marc R. [Univ. of Washington, Seattle, WA (United States)] (ORCID:0000000294359051)·Rossi, Andrew W. [Univ. of Washington, Seattle, WA (United States)] (ORCID:000000017588534X)·Masiello, David J. [Univ. of Washington, Seattle, WA (United States)] (ORCID:0000000211870920)
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Abstract

Chiral phonons possessing valley pseudoangular momentum (PAM) underlie a diversity of quantum phenomena of fundamental and applied importance, but are challenging to probe directly. We show that deficiencies of typical momentum-resolved electron energy loss measurements that make it impossible to distinguish the PAM of chiral phonons can be overcome by introducing pinwheel free electron states with well-defined PAM. Transitions between such states generate 2D periodic arrays of in-plane field vortices with polarization textures tailored to selectively couple to desired chiral mode symmetries.

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chiralityelectron energy loss spectroscopyphononsscanning transmission electron microscopyspin texturetopological materials

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BibTeXRIS

Bourgeois, Marc R. [Univ. of Washington, Seattle, WA (United States)] (ORCID:0000000294359051), Rossi, Andrew W. [Univ. of Washington, Seattle, WA (United States)] (ORCID:000000017588534X), Masiello, David J. [Univ. of Washington, Seattle, WA (United States)] (ORCID:0000000211870920). 2025-01-14. Strategy for Direct Detection of Chiral Phonons with Phase-Structured Free Electrons. https://doi.org/10.1103/physrevlett.134.026902

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