We discuss the design and demonstration of various III–V/Si asymmetric Mach–Zehnder interferometer (AMZI) and ring-assisted AMZI (de-)interleavers operati

We discuss the design and demonstration of various III–V/Si asymmetric Mach–Zehnder interferometer (AMZI) and ring-assisted AMZI (de-)interleavers operating at O-band wavelengths with 65 GHz channel spacing. The wafer-bonded III–V/Si metal-oxide-semiconductor capacitor (MOSCAP) structure facilitates ultra-low-power phase tuning on a heterogeneous platform that allows for complete monolithic transceiver photonic integration. The second- and third-order MOSCAP AMZI (de-)interleavers exhibit cross-talk (XT) levels down to -22 dB and -32dB with tuning powers of 83.0 nW and 53.0 nW, respectively. The one-, two-, and three-ring-assisted MOSCAP AMZI (de-)interleavers have XT levels down to -27 dB, -22 dB, and -20dB for tuning powers of 10.0 nW, 7220.0 nW, and 33.6 nW, respectively. The leakage current density is measured to be in the range of 1.6–27μA/cm2. To the best of our knowledge, we have demonstrated for the first time, athermal III–V/Si MOSCAP (de-)interleavers with the lowest XT and reconfiguration power consumption on a silicon platform.show less

We demonstrate four-wave mixing (FWM) in the graphdiyne (GDY) microfiber based on the synchronized dual-wavelength pump pulses that are transformed from a

We demonstrate four-wave mixing (FWM) in the graphdiyne (GDY) microfiber based on the synchronized dual-wavelength pump pulses that are transformed from a mode-locked fiber laser. Benefiting from the large nonlinear refractive index of GDY and the synchronized pump pulses, a maximum conversion efficiency of -39.05 dB can be achieved in GDY with only an average pump power of 6.9 mW, greatly alleviating the possible damage compared to previous investigations employing the continuous-wave pump. In addition, our proposal can be applied to measure the effective nonlinear coefficient γ of the GDY-microfiber, which could be extended as a practical measurement tool for γ of nanomaterials-based devices.show less

This paper presents quantitative measurements facilitated with a new optical system that implements a single-shot three-input phase retrieval algorithm. T

This paper presents quantitative measurements facilitated with a new optical system that implements a single-shot three-input phase retrieval algorithm. The new system allows simultaneous acquisition of three distinct input patterns, thus eliminating the requirement for mechanical movement and reducing any registration errors and microphonics. We demonstrate the application of the system for measurement and separation of two distinct attenuation measurements of surface waves, namely, absorption and coupling loss. This is achieved by retrieving the phase in the back focal plane and performing a series of virtual optics computations. This overcomes the need to use a complicated series of hardware manipulations with a spatial light modulator. This gives a far more accurate and faster measurement with a simpler optical system. We also demonstrate that phase measurements allow us to implement different measurement methods to acquire the excitation angle for surface plasmons. Depending on the noise statistics different methods have superior performance, so the best method under particular conditions can be selected. Since the measurements are only weakly correlated, they may also be combined for improved noise performance. The results presented here offer a template for a wider class of measurements in the back focal plane including ellipsometry.show less

It is a challenging problem to balance the modal walk-off (modal dispersion) between multiple transverse modes and chromatic dispersion in long step-index

It is a challenging problem to balance the modal walk-off (modal dispersion) between multiple transverse modes and chromatic dispersion in long step-index multimode fibers (MMFs). By properly designing the oscillator, we have overcome the difficulty and successfully obtained an all-fiber spatiotemporal mode-locked laser based on step-index MMFs with large modal dispersion for the first time, to our knowledge. Various proofs of spatiotemporal mode-locking (STML) such as spatial, spectral, and temporal properties, are measured and characterized. This laser works at a fundamental frequency of 28.7 MHz, and achieves a pulse laser with single pulse energy of 8 nJ, pulse width of 20.1 ps, and signal-to-noise ratio of ∼70dB. In addition, we observe a dynamic evolution of the transverse mode energy during the STML establishment process that has never been reported before.show less