Resolving the Orientations of and Angular Separation Between a Pair of Dipole Emitters

2025/03/07 by Y. N. Chen, Yuanxin Qiu, Matthew D. Lew · 1 voice · 2 citations
Engineering · Physics and Astronomy · #Near-Field Optical Microscopy #Orbital Angular Momentum in Optics #Photonic and Optical Devices

paper · doi:10.1103/physrevlett.134.093805

openalex publication_date 2025/03/07 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/30

Abstract

We prove that it is impossible to distinguish two spatially coinciding fluorescent molecules from a single rotating molecule using polarization-sensitive imaging, even if one modulates the polarization of the illumination or the detection dipole-spread function (DSF). If the target is known to be a dipole pair, existing imaging methods perform poorly for measuring their angular separation. We propose simultaneously modulating the excitation polarization and DSF, which demonstrates robust discrimination between dipole pairs versus single molecules. Our method improves the precision of measuring centroid orientation by 50% and angular separation by two- to four-fold over existing techniques.

Citations

• Single-molecule orientation-localization microscopy: Applications and approaches
• Extending fluorescence anisotropy to large complexes using reversibly switchable proteins
• Six-dimensional single-molecule imaging with isotropic resolution using a multi-view reflector microscope

Cited by

• Painting rich six-dimensional pictures using polarized fluorescence microscopy
• Single-molecule orientation and localization microscopy

Discussions

• Happy to share #YiyangChen17 's article in #PhysRevLett! What happens when you use a #polarization #microscope to look at a pair of molecules? They look like a #wobbling #singlemolecule! No 🔬 can tel [bsky, 7 points, 0 comments]

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