Broadband Parametric Amplification in AlGaAs‐on‐Insulator Nanowaveguides

ABSTRACT Optical amplification is critical for optical signal transmission. While the emergence of erbium‐doped fiber amplifiers has revolutionized optical communications in fiber‐based systems, on‐chip amplification is still needed for integrated optics. Since nanoscale waveguides enhance nonlinearity by several orders of magnitude, they are promising candidates for optical parametric amplification. Using a pulsed pump at 1550 nm, broadband optical parametric amplification based on four‐wave mixing is investigated in AlGaAs‐on‐insulator nanowaveguides. The intense nonlinearity enables an on–off gain as large as 58.4 dB. Meanwhile, the low propagation loss leads to a 56.2‐dB net on‐chip gain. Combined with further dispersion engineering, the net on‐chip gain bandwidth extends beyond 415 nm. The demonstrated results represent the largest parametric gain and bandwidth reported for on‐chip parametric amplifiers.