14 research outputs found
Light-induced dynamic frequency shifting of microwave photons in a superconducting electro-optic converter
Hybrid superconducting-photonic microresonators are a promising platform for
realizing microwave-to-optical transduction. However, the absorption of
scattered photons by the superconductors leads to unintended microwave
resonance frequency variation and linewidth broadening. Here, we experimentally
study the dynamics of this effect and its impact on microwave-to-optics
conversion in an integrated lithium niobate-superconductor hybrid resonator
platform. We unveiled an adiabatic frequency shifting of the intracavity
microwave photons induced by the fast photo-responses of the thin-film
superconducting resonator. As a result, the temporal and spectral responses of
electro-optics transduction are modified and well described by our theoretical
model. This work provides important insights on the light-induced conversion
dynamics which must be considered in future designs of hybrid
superconducting-photonic system
Unveiling the origins of quasi-phase matching spectral imperfections in thin-film lithium niobate frequency doublers
Thin-film lithium niobate (TFLN) based frequency doublers have been widely
recognized as essential components for both classical and quantum optical
communications. Nonetheless, the efficiency of these devices is hindered by
imperfections present in the quasi-phase matching (QPM) spectrum. In this
study, we present a thorough analysis of the spectral imperfections in TFLN
frequency doublers with varying lengths, ranging from 5 mm to 15 mm. Employing
a non-destructive diagnostic method based on scattered light imaging, we
identify the sources and waveguide sections that contribute to the
imperfections in the QPM spectrum. Furthermore, by mapping the TFLN film
thickness across the entire waveguiding regions, we successfully reproduce the
QPM spectra numerically, thus confirming the prominent influence of film
thickness variations on the observed spectral imperfections. This comprehensive
investigation provides valuable insights into the identification and mitigation
of spectral imperfections in TFLN-based frequency doublers, paving the way
toward the realization of nonlinear optical devices with enhanced efficiency
and improved spectral fidelity