High-power handling and bias stability of thin-film Lithium Tantalate microring and coupling resonators

TL;DR

This paper demonstrates high-power handling and stable bias operation of thin-film lithium tantalate microring resonators, enabling efficient electro-optic modulation with minimal frequency shifts and no photo-refractive effects.

Contribution

It introduces annealed oxide-cladded TFLT resonators capable of handling several watts and a compact low-voltage modulator with stable bias in the telecom C-band.

Findings

Resonators handle 4W circulating power with minimal frequency shift.

Achieved a low Vpi of 3V in a 2mm coupling modulator.

No observable photo-refractive effects during high-power operation.

Abstract

In this paper, we demonstrate the ultra-high-power handling capability and DC bias stability of optical microring and electro-optic (EO) coupling resonators on the thin-film lithium tantalate (TFLT) platform. We show that, with annealing, oxide-cladded TFLT resonators can handle several watts (4W) of circulating power with minimal frequency shift and no observable photo-refractive effect. Furthermore, we demonstrate a compact 2mm coupling modulator achieving a low Vpi of 3V with stable bias and phase control in the telecom C-band.