Third-harmonic generation in CMOS-compatible highly doped silica micro-ring resonator

Abstract

We present the first demonstration of visible emission from highly doped silica glass micro-ring resonators (MRRs) through a third-harmonic generation (THG) nonlinear process. We obtain green light conversion efficiency of 2.7×10−5 W−2 in a MRR with loaded Q-factor of 1.4×106 pumped in the telecom band. A thermal nonlinear model is developed to account for the in-cavity power dependence of the resonance detuning. Using the extracted thermal nonlinear coefficients, the measured TH resonance shift is calibrated by subtracting the thermal nonlinear-induced phase mismatch to obtain the theoretical threefold wavelength relationship along with the measured cubic power relationship.

Nonlinear nanophotonic devices in the ultraviolet to visible wavelength range

“…These other phase matching conditions (including quasi-phase matching) are often referred to as Type 0 phase matching. One example is using modal dispersion to phase-match, which may depend on material choices and/or the specific geometry of the device [58,59]. In modal dispersion phase matching, the device is designed such that the effective refractive index of the modes supporting the pump and generated (second-harmonic or third-harmonic) frequencies match.…”

Athermal third harmonic generation in micro-ring resonators

“…Such difference is about 10 times greater than that in the Si 3 N 4 MRR 17 . Meanwhile, both of these platforms have similar linear TDWS at around 20 pm/°C [13][14][15][16][17][18] . It indicates that in the HDSG MRRs, the nonlinear TO effect can redshift the resonance of pump mode over a much broader bandwidth of about 10 times compared to the Si 3 N 4 MRR.…”

“…2 in ref. 13 , respectively. The advantage of the device having a drop port is to allow the direct monitoring of I p .…”

“…Nonlinear high-harmonic generation in micro-resonators using a pump at telecom wavelengths is a popular technique used to extend the operating range of applicationfs such as f-2f and 2f-3f self-referencing systems and coherent communications in the visible region [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16] . Recent demonstration of visible emission generation in microring resonators (MRRs) via third-harmonic generation (THG) in a number of nonlinear integrated optical circuit platforms, such as silicon nitride [7][8][9] , composite AlN/Si 3 N 4 [10][11] , lithium niobite (LN) on insulator 12 , and highly doped silica glass (HDSG) 13 , promises the potential of on-chip integration of a visible reference source in the advanced integrated circuits using these platforms. This is especially important in the development of compact and practical self-referencing and sensing systems.…”