We propose a multi-layered, 2D optical phased array capable of 180° × 180° beam steering range without wavelength tuning. Evanescent coupling between half-wavelength spaced waveguides is suppressed below −20 dB through index-mismatch and extreme skin-depth metamaterial waveguides.

We present an OPA with uniform half-wavelength pitch and grating emitters. Aliasing-free beam steering over ∼ 120° field-of-view is measured. Evanescent coupling between closely spaced emitters is suppressed by extreme skin-depth cladding structures.

We report phase retrieval of a single-soliton Kerr comb using electric field cross-correlation implemented via dual-comb interferometry. The phase profile of the Kerr comb is acquired through the heterodyne beat between the Kerr comb and an electro-optic comb with a pre-characterized phase profile. The soliton Kerr comb has a nearly flat phase profile, and the pump line is observed to show a phase offset which depends on the pumping parameters. The experimental results are in agreement with numerical simulations.

A TE0 block TE1 pass filter is proposed and experimentally demonstrated on SOI platform over C band. The filter suffers negligible reflection and is theoretically immune to phase dependent spectral fluctuation under dual-modes concurrent input.

We demonstrate all-linear phase retrieval of a single-soliton Kerr comb via dual-comb electric field cross-correlation (EFXC). This approach greatly lowers the power needed for ultrafast waveform reconstruction of optical frequency combs.

We propose a 3-micron-radius, TE0/TE1 multiplexed 90-degree bend that numerically exhibits 0.8 dB bending loss and 20 dB crosstalk suppression over 30nm bandwidth on an silicon-on-insulator platform. An S-bend shows >37 dB colorless crosstalk suppression.

Ultrafast optical pulse shaping supports a broad number of applications, ranging from ultrafast time-resolved spectroscopy to RF photonics [1]. Conventional pulse shapers rely on bulk optics and use liquid crystal spatial light modulators, with reconfiguration times limited to milliseconds. Integrated optical pulse shapers offer not only size advantage but also the potential for much faster reconfiguration by using electro-optic pulse shaping elements. Integrated pulse shapers usually employ an arrayed waveguide grating (AWG) to separate the input light into its constituent wavelengths, process each wavelength band using an array of on-chip components, and then recombine the light again relying on AWG action. AWG-based integrated pulse shapers with independent thermo-optic amplitude and phase control have been demonstrated in silica, but the reconfiguration time remains limited [2]. Our group previously reported a 32-channel InP arrayed waveguide grating pulse shaper (AWGPS) with 25 GHz channel spacing and an array of semiconductor optical amplifiers (SOAs) for spectral amplitude control. This work demonstrated amplitude shaping fidelity good enough to apply to RF photonic bandpass filtering with sidelobe suppression >35 dB as well as microsecond-scale reconfiguration [3]. Other groups have also demonstrated pulse shaping with integrated InP with either amplitude or phase control but not both [4]. In this work we report preliminary characterization of a 48 channel InP shaper at 50 GHz channel spacing, provisioned with both channel-by-channel phase adjusters and SOA gain elements (Fig. 1). To our knowledge this constitutes the first demonstration of an operable integrated InP pulse shaper with independent intensity and phase control.

We report on a compact passive mode-locked Er:fiber ring laser operated at the fundamental repetition rate of 517 MHz, which we believe is the highest fundamental repetition rate ever reported in a ring cavity fiber laser. The key technique is the employment of two innovative high-power wavelength domain multiplexer collimators with all gain fiber cavity suited for the high power (up to 2 W) pumping. The laser is featured with a direct chirp-free output pulse, which is 97 fs without extracavity compression at an average output power of 90 mW.

Objective To build a low repetition rate femtosecond fiber laser with its pulse width narrower than 200 fs and pulse energy bigger than 50 nJ and realize making blasting holes on pig cornea by optical expanding and focusing femtosecond laser.Methods Experimental study.Introducing very long polarization maintaining fiber into the ring cavity,the mode-locking fiber laser under the similariton amplifier scheme was used to be the oscillator.The signal laser was amplified and compressed by propagating it through the construction of pre-chirp,amplifier and de-chirp to realize outputting high quality pulse train.The high power fiber laser was expanded by the lens group.The expanded laser beam was focused into the pig cornea by the plane objective with different numerical aperture (NA) to realize making high quality blasting holes.Results This laser facility realized outputing a very stable 19.1 MHz,109 fs,1.4 W,73.2 nJ mode-locking fiber laser.After five fold expansion,the laser beam was focused into the pig cornea by the NA=0.2 plane objective to get blasting holes whose aperture were 45～75 μm.Focusing the laser beam into the pig cornea by the NA=0.5 plane objective,the aperture of the blasting holes were about 30 μm.Conclusion Introducing very long Polarization Maintaining fiber into the similariton amplifier ring cavity can improve stability effectively.The construction of pre-chirp,amplifier and de-chirp can use the nonlinear affects to depress the third order dispersion to realize high quality amplify and compression.After expanded by lens group,using higher NA plane objective to focus the expanded laser beam into the cornea can realize making higher quality blasting holes.

We demonstrate an astro-comb for relatively low resolution astronomical spectrographs. The space of comb lines is Altered to 30 GHz by a Fabry-Perot cavity spaced by an ULE glass. The radial velocity precision is <40 cm/s.