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Nanoscale disorder results in severe spectral misalignment of silicon microring resonators and Mach-Zehnder interferometers. We correct for such effects using electric-field-induced waveguide nano-oxidation, demonstrating a tuning wavelength range of several nanometers and 0.002 nm resolution without line shape degradation. Field-induced nano-oxidation is a permanent and precise technique and requires no new materials or high-temperature processing.

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We developed a simple method to construct liquid-core/PDMS-cladding optical waveguides through pressurized filling of dead-ended micro-channels with optical fluids. The waveguides are in the same layer as microfluidic channels which greatly simplifies device fabrication. With proper contrast between the refractive index of the core and cladding, the transmission loss of the waveguides is less than 5 dB cm(-1). We also developed a method to create flat and optically clear surfaces on the sides of PDMS devices in order to couple light between free-space and the waveguides embedded inside the chip. With these newly developed techniques, we make a compact flow cytometer and demonstrate the fluorescence counting of single cells at a rate of up to ~50 cell s(-1) and total sample requirement of a few microlitres. This method of making liquid-core optical waveguides and flat surfaces has great potential to be integrated into many PDMS-based microsystems.

A meminductor is a new type of memory device developed from the memristor. We present a mathematical model of a flux-controlled meminductor and its equivalent circuit model for exploring the properties of the meminductor in a nonlinear circuit. We explore the response characteristics of the meminductor under the exciting signals of sinusoidal, square, and triangular waves by using theoretical analysis and experimental tests, and design a meminductor-based oscillator based on the model. Theoretical analysis and experiments show that the meminductor-based oscillator possesses complex bifurcation behaviors and can generate periodic and chaotic oscillations. A special phenomenon called the co-existent oscillation that can generate multiple oscillations (such as chaotic, periodic oscillations as well as stable equilibrium) with the same parameters and different initial conditions occurs. We also design an analog circuit to realize the meminductor-based oscillator, and the circuit experiment results are in accordance with the theory analysis.