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A proof-of-concept for a new and entirely CMOS compatible thermo-optic reconfigurable switch based on a coupled ring resonator structure is experimentally demonstrated in this paper. Preliminary results show that a single optical device is capable of combining several functionalities, such as tunable filtering, non-blocking switching and reconfigurability, in a single device with compact footprint (~50µm x 30µm).

A proof-of-concept for a new and entirely CMOS compatible tunable nanobeam cavity is demonstrated in this paper. Preliminary results show that a compact nanobeam cavity (~20 μm 2 ) with high Q-factor (~50,000) and integrated with a micro-heater atop, is able of tuning the resonant wavelength up to 15 nm with low power consumption (0.35nm/mW), and of attaining high modulation depth with only ~100 μW. Additionally, a tunable bi-stable behavior is reported.

This study reports on negative group velocities in a lumped transmission line, where capacitors and inductors connected to resistors are placed in the series and shunt branches of the periodic line, respectively. The propagation characteristics of the left‐handed transmission line are examined along with two methods. The first method consists of analysing the lumped‐element ladder network by solving in the time domain a system of differential equations derived from the Kirchhoff's voltage and current laws. In the second method, transmission matrix of the unit cell is applied to obtain the dispersion diagram from which the time group delay induced by the periodic network is derived as a function of frequency. Also, non‐analytical input signals are considered, whereby transient effects occur at both ends of modulated half‐sine wave packets propagating under negative group delay (NGD) regime of the left‐handed line. NGD effects arise from ohmic dissipation due to the resistors which establish a frequency range in which NGD propagation is allowed. This finding is numerically demonstrated by injecting into the line modulated Gaussian wave packets, for which the negative time delays determined from the numerical solution of circuit equations and from the dispersion relation are in good agreement.

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