Optical microring resonators in fluorineimplanted lithium niobate.
We report on the production and characterisation of optical microring resonators and optical channel waveguides by using fluorine-ion implantation and planar structuring in lithium niobate. We demonstrate the production of single-mode planar waveguides by low fluence fluorine-ion implantation (?? = 2.5 x10(14) ions/cm(2)) into lithium niobate wafers. The waveguides are strongly confined by the amorphous 2-microm wide optical barrier induced by the implantation process. A refractive index contrast of Deltan(o) = 0.17 at the telecom wavelength lambda = 1.5 microm has been determined between the waveguide and the barrier. Planar structuring with ridge height of up to 1.2 microm has been achieved by laser lithography masking and Ar(+) sputtering. For TE waves, the channel waveguides exhibit propagation losses lower than 8 dB/cm. First ring resonators with 80-microm radius have been fabricated by planar structuring in fluorine-ion implanted lithium niobate. The measured resonance curves show an extinction ratio of 14 dB, a free spectral range of 2.0 nm and a finesse of 4.
Nonlinear Optics Laboratory, Institute of Quantum Electronics, ETH Zurich, CH-8093 Zurich, Switzerland. majkic@phys.ethz.ch
Aleksej
A
Majkic
Manuel
M
Koechlin
Gorazd
G
Poberaj
Peter
P
Günter
D005461:Fluorine / Q000737:chemistry*; D009556:Niobium / Q000737:chemistry*; D055095:Optics and Photonics / Q000295:instrumentation*; D010087:Oxides / Q000737:chemistry*; D014159:Transducers; D014732:Vibration
D010087:Oxides; D009556:Niobium; C091692:lithium niobate; D005461:Fluorine