Integrated optical auto-correlator based on third-harmonic generation in a silicon photonic crystal waveguide

Abstract

The ability to use coherent light for material science and applications is linked to our ability to measure short optical pulses. While free-space optical methods are well established, achieving this on a chip would offer the greatest benefit in footprint, performance and cost, and allow the integration with complementary signal-processing devices. A key goal is to achieve operation at sub-watt peak power levels and on sub-picosecond timescales. Previous integrated demonstrations require either a temporally synchronized reference pulse, an off-chip spectrometer or long tunable delay lines. Here we report a device capable of achieving single-shot time-domain measurements of near-infrared picosecond pulses based on an ultra-compact integrated CMOS-compatible device, which could operate without any external instrumentation. It relies on optical third-harmonic generation in a slow-light silicon waveguide. Our method can also serve as an in situ diagnostic tool to map, at visible wavelengths, the propagation dynamics of near-infrared pulses in photonic crystals.

Nonlinear optical response of low loss silicon germanium waveguides in the mid-infrared

“…The RMS spectral broadening calculated from the different simulation scenarios are compared to the experimental ones in Fig. 8(b) and demonstrate that including both n 2 and n 4 gives the better agreement with the experimental results of both Figs. 8(a) and 8(b).…”

“…Sensing applications require compact and low-cost optical devices and, most importantly, optical sources that are widely tuneable or yield broadband emission to access the whole mid-IR band. There have been a number of approaches, particularly within the silicon photonics community [3][4][5][6], to adapt technologies developed for the near-IR to the mid-IR for both linear [1,2,[7][8][9][10][11] and nonlinear photonic devices. For nonlinear devices, the issue of two-photon absorption (TPA) that limits device performance in the near-infrared region, vanishes at longer wavelengths (>2.2 μm) [1,3], and this has motivated some impressive nonlinear optical demonstrations in silicon on insulator (SOI) waveguides near 2 μm [7,10], as well as in silicon on sapphire (SOS) [11].…”

Reconfigurable broadband microwave photonic intensity differentiator based on an integrated optical frequency comb source

“…[1][2][3][4][5][6] As one of the basic building blocks in optical signal processing and computing systems, 7 differentiators are a key requirement in analyzing high-speed signals as well as in waveform shaping, pulse generation, and systems control. [8][9][10] To implement photonic differentiators, a number of schemes have been proposed, which can be classified into two categories, namely, field differentiators and intensity differentiators.…”

Ultra-high Q/V hybrid cavity for strong light-matter interaction

“…[1][2][3] This confinement enhances the light-matter interaction and enables a number of interesting applications, e.g., in optical communications, quantum electrodynamics (QED), 4 enhanced spontaneous emission, 5 non-linear optics, 6 biosensing, 7 and optical trapping. 8 A high Q/V can be achieved either by increasing the Q, as in dielectric cavities, or by decreasing the V, as in plasmonic cavities.…”