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arXiv · 2204.12078

Integrated Pockels Laser

Abstract

The development of integrated semiconductor lasers has miniaturized traditional bulky laser systems, enabling a wide range of photonic applications. A progression from pure III-V based lasers to III-V/external cavity structures has harnessed low-loss waveguides in different material systems, leading to significant improvements in laser coherence and stability. Despite these successes, however, key functions remain absent. In this work, we address a critical missing function by integrating the Pockels effect into a semiconductor laser. Using a hybrid integrated III-V/Lithium Niobate structure, we demonstrate several essential capabilities that have not existed in previous integrated lasers. These include a record-high frequency modulation speed of 2 exahertz/s (2.0$\times$10$^{18}$ Hz/s) and fast switching at 50 MHz, both of which are made possible by integration of the electro-optic effect. Moreover, the device co-lases at infrared and visible frequencies via the second-harmonic frequency conversion process, the first such integrated multi-color laser. Combined with its narrow linewidth and wide tunability, this new type of integrated laser holds promise for many applications including LiDAR, microwave photonics, atomic physics, and AR/VR.

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Mingxiao Li, Lin Chang, Lue Wu, Jeremy Staffa, Jingwei Ling, Usman A. Javid, Yang He, Raymond Lopez-rios, Shixin Xue, Theodore J. Morin, Boqiang Shen, Heming Wang, Siwei Zeng, Lin Zhu, Kerry J. Vahala, John E. Bowers, Qiang Lin. 2022-04-26. Integrated Pockels Laser. https://doi.org/10.1038/s41467-022-33101-6

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