Investigation of low-power comb generation in silicon microresonators from dual pumps

Abstract

Here, the influence of pump powers for silicon microresonator-based Kerr comb generation (KCG) was investigated theoretically and experimentally in two types of dual-pumped KCG. One employs dual pumps at different free spectral range (FSR) spacings of the resonator for broadband comb spectrum and the other to produce comb lines at one FSR spacing for low pump powers. The KCG is modeled by including nonlinear absorption and mode interaction into the Lugiato–Lefever equation. Both the theoretical and the experimental results indicate that the KCG with pump powers inside the ring of tens of milliwatts would be limited by high nonlinear absorption even with a 25 V reverse bias to deplete free carriers. The most efficient comb spectrum occurs with recirculating pump power in the ring cavity of 13 mW (0.3 mW pump power in the bus waveguide) at 25 V reverse bias. Generally, for silicon KCG at the telecom wavelengths, the use of low pump powers and reverse bias is essential. At 25 V reverse bias, increasing the stored pump power in the ring to 160 mW would suppress the KCG and produce a similar number of comb lines as 1 mW recirculating pump power. This work advances our understandings of silicon KCG in the telecom band.

Fully integrated and broadband Si-rich silicon nitride wavelength converter based on Bragg scattering intermodal four-wave mixing

“…In this regard, configurations multiple spectral bands of the electromagnetic spectrum, even located hundreds of nanometers away from the pump source(s) [11,12]. Several demonstrations of IM-based applications have already been shown, such as supercontinuum generation [13][14][15], comb generation [16,17], signal processing based on stimulated IM Brillouin scattering [18,19], wavelength conversion [12,[20][21][22][23][24] and the realization of photon pair sources for quantum applications [25][26][27]. Most of these demonstrations made use of either degenerate or non-degenerate parametric amplification, where the idler generation is accompanied by the amplification of vacuum fluctuations, which inherently adds excess noise to the process [28,29].…”

Temporal evolution and spectral characteristics of dual field in a double-pumped microcavity

“…In addition, another pumping technique for a single microcavity is suggested. Two separate lasers with completely orthogonal polarizations pump the microcavity [27][28][29]. Two modes can be excited inside a microcavity using this configuration.…”