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arXiv · 2209.07123

A quantum logic gate for free electrons

Stefan Löffler·Thomas Schachinger·Peter Hartel·Peng-Han Lu·Rafal E. Dunin-Borkowski·Martin Obermair·Manuel Dries·Dagmar Gerthsen·Peter Schattschneider
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Abstract

The topological charge $m$ of vortex electrons spans an infinite-dimensional Hilbert space. Selecting a two-dimensional subspace spanned by $m=\pm 1$, a beam electron in a transmission electron microscope (TEM) can be considered as a quantum bit (qubit) freely propagating in the column. A combination of electron optical quadrupole lenses can serve as a universal device to manipulate such qubits at the experimenter's discretion. We set up a TEM probe forming lens system as a quantum gate and demonstrate its action numerically and experimentally. High-end TEMs with aberration correctors are a promising platform for such experiments, opening the way to study quantum logic gates in the electron microscope.

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Stefan Löffler, Thomas Schachinger, Peter Hartel, Peng-Han Lu, Rafal E. Dunin-Borkowski, Martin Obermair, Manuel Dries, Dagmar Gerthsen, Peter Schattschneider. 2022-09-15. A quantum logic gate for free electrons. https://doi.org/10.22331/q-2023-07-11-1050

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