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arXiv · 2111.13130

Quantum states interrogation using a pre-shaped free electron wavefunction

Bin Zhang·Du Ran·Reuven Ianconescu·Aharon Friedman·Jacob Scheuer·Amnon Yariv·Avraham Gover
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Abstract

We present a comprehensive theory for interrogation of the quantum state of a two-level system (TLS) based on a free-electron - bound-electron resonant interaction scheme. The scheme is based on free electrons, whose quantum electron wavefunction is pre-shaped or optically modulated by lasers in an electron microscope setup and then inelastically scattered by a quantum TLS target (e.g., atom, quantum dot, crystal defect center, etc.) upon traversing in proximity to the target. Measurement of the post-interaction energy spectrum of the electrons, probes and quantifies the full Bloch sphere parameters of a pre-excited TLS and enables coherent control of the qubit states. The exceptional advantage of this scheme over laser-based ones is the atomic-scale spatial resolution of addressing individual TLS targets. Thus, this scheme opens new horizons for electron microscopy in material interrogation and quantum information technology.

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Bin Zhang, Du Ran, Reuven Ianconescu, Aharon Friedman, Jacob Scheuer, Amnon Yariv, Avraham Gover. 2021-11-25. Quantum states interrogation using a pre-shaped free electron wavefunction. https://arxiv.org/abs/2111.13130

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