Efficient continuous-wave four-wave mixing in bandgap-engineered AlGaAs waveguides

Abstract

We present a side-by-side comparison of the nonlinear behavior of four passive AlGaAs ridge waveguides where the bandgap energy of the core layers ranges from 1.60 to 1.79 eV. By engineering the bandgap to suppress two-photon absorption, minimizing the linear loss, and minimizing the mode area, we achieve efficient wavelength conversion in the C-band via partially degenerate four-wave mixing with a continuous-wave pump. The observed conversion efficiency [Idler(OUT)/Signal(IN)=-6.8 dB] is among the highest reported in passive semiconductor or glass waveguides.

Nonlinear properties of dispersion engineered InGaP photonic wire waveguides in the telecommunication wavelength range

“…The 1/T 2 trend however is linear with respect to the square of the input peak power as shown in Fig. 4(b) which points towards three-photon absorption being the dominant multi-photon loss mechanism in these InGaP photonic wires [14,15]…”

“…Heterogeneously integrated III-V materials on a silicon substrate have already been extensively studied for on-chip light generation [11][12][23][24]. Previous studies have explored the nonlinear properties of photonic wire waveguides and photonic crystal waveguides realized on their III-V growth substrate based on different III-V materials, including InGaP, for a range of nonlinear optics applications [14][15][16][17][18][19]22].…”

Characterization and Optimization of a High-Efficiency AlGaAs-On-Insulator-Based Wavelength Converter for 64- and 256-QAM Signals

“…A material platform offering high nonlinearity, low propagation loss and a bandgap ensuring TPA-free operation at telecom wavelength is highly desired. AlGaAs has been shown to provide large intrinsic nonlinearity (n 2 ≈ 10 −17 W/m 2 ), and no TPA around 1550 nm [21]- [24]. To further enhance the effective nonlinearity, we have previously demonstrated the AlGaAs-on-insulator (AlGaAsOI) platform, where moderately low propagation loss (≤ 1.5 dB/cm) high-index contrast nanowaveguides can be realized with a high nonlinear coefficient.…”

Integrated nonlinear photonics: emerging applications and ongoing challenges [Invited]

“…More recently, a-Si:H has provided wavelength conversion performance competitive with c-Si in both bandwidth (20 THz) and conversion efficiencies (−13 dB) with significantly reduced pump power requirements of only 15 mW [9] as a result of its ultrahigh nonlinear refractive index. Additionally of note is the recent demonstration in the compound semiconductor AlGaAs, where a FWM conversion efficiency of −6.4 dB with ∼600 mW of peak power was achieved in CW operation [10] through a combination of bandgap engineering to avoid two-photon absorption (TPA) and a unique technique involving plasma-assisted resist reflow for ultralow propagation loss for the waveguide fabrication of this traditionally lossy platform [11].…”