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arXiv · 2411.00170

Compact optical waveform generator with digital feedback

Shuzhe Yang·Guido Masella·Vase Moeini·Amar Bellahsene·Chang Li·Tom Bienaimé·Shannon Whitlock
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Abstract

A key requirement for quantum technologies based on atoms, ions, and molecules, is the ability to realize precise phase- and amplitude-controlled quantum operations via coherent laser pulses. However, for generating pulses on the sub-microsecond timescale, the characteristics of the optical and electronic components can introduce unwanted distortions that have a detrimental effect on the fidelity of quantum operations. In this paper, we present a compact arbitrary waveform generator that integrates a double-pass acousto-optic modulator for user-specified laser amplitude and phase modulations. Additionally, the module integrates an optical heterodyne detector to extract the precise laser pulse shape in real-time. The measured pulse shape is then fed into a digital feedback loop used to estimate the complex-valued transfer function and pre-distorted input pulses. We demonstrate the performance by generating shaped laser pulses suitable for realizing quantum logic gates with durations down to 180\,ns, requiring only a small number of feedback iterations.

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Shuzhe Yang, Guido Masella, Vase Moeini, Amar Bellahsene, Chang Li, Tom Bienaimé, Shannon Whitlock. 2024-10-31. Compact optical waveform generator with digital feedback. https://doi.org/10.1103/physrevapplied.23.054009

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