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arXiv · 2405.01826

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

Marc R. Bourgeois·Andrew W. Rossi·David J. Masiello
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Abstract

Chiral phonons possessing valley pseudo angular 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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Marc R. Bourgeois, Andrew W. Rossi, David J. Masiello. 2024-05-03. Strategy for Direct Detection of Chiral Phonons with Phase-Structured Free Electrons. https://arxiv.org/abs/2405.01826

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