Resolving and resetting the charge environment of single T-centers in silicon p-i-n waveguides

Chaoshen Zhang; Hanbin Song; Lukasz Komza; Aaron M. Day; Enrique Garcia; Donald Witt; Mihir K. Bhaskar; Alp Sipahigil; Evelyn L. Hu

arXiv · 2608.15993

Resolving and resetting the charge environment of single T-centers in silicon p-i-n waveguides

Chaoshen Zhang·Hanbin Song·Lukasz Komza·Aaron M. Day·Enrique Garcia·Donald Witt·Mihir K. Bhaskar·Alp Sipahigil·Evelyn L. Hu

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Abstract

The silicon T-center is a telecom-band spin-photon interface in a manufacturable photonics platform. In nanophotonic devices, however, its optical linewidth is broadened by a fluctuating charge environment, limiting photon indistinguishability for quantum networking. Here, we address this challenge through characterization and suppression of the local charge-noise of single T-centers in lateral p-i-n waveguides, demonstrating an unheralded method of T-center optical linewidth narrowing. Above-band illumination resets the charge environment, neutralizing the local field and suppressing spectral diffusion. Across 46 emitters this reset narrows the median linewidth 3.5-fold to 0.57(11) GHz, and an optimized emitter reaches 128(22) MHz, the narrowest unheralded linewidth reported for an integrated T-center. The narrowed transition supports coherent optical Rabi oscillations with a coherence time of 20(2) ns. Finally, we perform Stark-shift tuning using the p-i-n junction, and read out the local electric field and the charge-noise width at 15 mK. An analytical model of proximal surfaces, bulk, and junction field effects provides good agreement with our findings. Our multi-pronged characterization of the nanophotonic-integrated T-center charge environment enables future device optimization toward scalable quantum interconnects.

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Chaoshen Zhang, Hanbin Song, Lukasz Komza, Aaron M. Day, Enrique Garcia, Donald Witt, Mihir K. Bhaskar, Alp Sipahigil, Evelyn L. Hu. 2026-08-17. Resolving and resetting the charge environment of single T-centers in silicon p-i-n waveguides. https://arxiv.org/abs/2608.15993

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