Fraunhofer-Gesellschaft

Publica

Hier finden Sie wissenschaftliche Publikationen aus den Fraunhofer-Instituten.

Electro-optic eigenfrequency tuning of potassium tantalate-niobate microresonators

 
: Szabados, Jan; Werner, Christoph; Herr, Simon J.; Breunig, Ingo; Buse, Karsten

:
Fulltext ()

APL photonics 5 (2020), No.1, Art. 016106, 7 pp.
ISSN: 2378-0967
English
Journal Article, Electronic Publication
Fraunhofer IPM ()
Frequency Combs; whispering gallery resonators; ferroelectric materials; electrooptical effects; Kerr Effects

Abstract
Eigenfrequency tuning in microresonators is useful for a range of applications including frequency-agile optical filters and tunable optical frequency converters. In most of these applications, eigenfrequency tuning is achieved by thermal or mechanical means, while a few non-centrosymmetric crystals such as lithium niobate allow for such tuning using the linear electro-optic effect. Potassium tantalate-niobate (KTa1−xNbxO3 with 0 ≤ x ≤ 1, KTN) is a particularly attractive material for electro-optic tuning purposes. It has both non-centrosymmetric and centrosymmetric phases offering outstandingly large linear as well as quadratic electro-optic coefficients near the phase transition temperature. We demonstrate whispering-gallery resonators made of KTN with quality factors of Q > 107 and electro-optic eigenfrequency tuning of more than 100 GHz at λ = 1040 nm for moderate field strengths of E = 250 V/mm. The tuning behavior near the phase transition temperature is analyzed by introducing a simple theoretical model. These results pave the way for applications such as electro-optically tunable microresonator-based Kerr frequency combs.

: http://publica.fraunhofer.de/documents/N-572340.html