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arXiv · 2601.19676

Optical steering of a large ring laser

Jannik Zenner·Karl Ulrich Schreiber·Simon Stellmer
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Abstract

A common approach to reduce the linewidth of a laser is an increase of its resonator length. In large gas lasers, however, the frequency spacing between longitudinal modes of the resonator easily becomes significantly smaller than the Doppler-broadened width of the gain profile. As a consequence, the laser might operate on a multitude of modes simultaneously, or jump between modes. Such unstable operation cannot be tolerated in metrological or sensing applications, such as ring laser gyroscopes. Here, we propose and demonstrate a method to establish stable operation on a chosen mode index by optically steering the ring laser to a desired mode index through injection locking with an external laser. The injected mode reliably follows the external steering. Intra-cavity backscattering can even cause the counter-propagating, non-injected mode to follow the external steering as well.

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Jannik Zenner, Karl Ulrich Schreiber, Simon Stellmer. 2026-01-27. Optical steering of a large ring laser. https://doi.org/10.1364/ol.591853

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