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arXiv · 2504.10994

Near-room-temperature zero-dimensional polariton lasers with sub-10 GHz linewidths

Ismael dePedro-Embid·Alexander S. Kuznetsov·Klaus Biermann·Andrés Cantarero·Paulo V. Santos
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Abstract

Narrow and brilliant spectral lines are essential assets for high-resolution spectroscopy as well as for precision sensing and optomechanics. In semiconductor structures and, in particular, in the well-established (Al,Ga)As material system, strong emission lines with nanosecond coherence times can be provided by the opto-electronic resonances of microcavity exciton-polariton condensates. The temporal coherence of these resonances, however, normally rapidly deteriorates as the temperature increases beyond a few tens of kelvins due to exciton dissociation. Here, we demonstrate that the temperature stability of polariton condensates in (Al,Ga)As can be significantly improved by confinement within micrometer-sized intracavity traps. We show that trapped condensates can survive up to ~200 K while maintaining a light-matter character with decoherence rates below 10 GHz (i.e., $< 40 μ$eV linewidths). These linewidths are by an order of magnitude smaller than those so far reported for other solid-state systems at these temperatures. Confinement thus provides a pathway towards room-temperature polariton condensation using the well-established (Al,Ga)As material system with prospects for application in scalable on-chip photonic devices for optical processing, sensing, and computing.

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Ismael dePedro-Embid, Alexander S. Kuznetsov, Klaus Biermann, Andrés Cantarero, Paulo V. Santos. 2025-04-15. Near-room-temperature zero-dimensional polariton lasers with sub-10 GHz linewidths. https://arxiv.org/abs/2504.10994

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