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arXiv · 2507.17993

On-Chip Laser-Driven Free-Electron Spin Polarizer

Clarisse Woodahl·Melanie Murillo·Charles Roques-Carmes·Aviv Karnieli·David A. B. Miller·Olav Solgaard
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Abstract

Spin-polarized electron beam sources enable studies of spin-dependent electric and magnetic effects at the nanoscale. We propose a method of creating spin-polarized electrons on an integrated photonics chip by laser driven nanophotonic fields. A two-stage interaction separated by a free space drift length is proposed, where the first stage and drift length introduces spin-dependent characteristics into the probability distribution of the electron wavefunction. The second stage uses an adjusted optical near-field to rotate the spin states utilizing the spin-dependent wavepacket distribution to produce electrons with high ensemble average spin expectation values. This platform provides an integrated and compact method to generate spin-polarized electrons, implementable with millimeter scale chips and table-top lasers.

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Clarisse Woodahl, Melanie Murillo, Charles Roques-Carmes, Aviv Karnieli, David A. B. Miller, Olav Solgaard. 2025-07-23. On-Chip Laser-Driven Free-Electron Spin Polarizer. https://doi.org/10.1103/3c1m-d3hh

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