Photonic integrated circuits are developing as key enabling components for high-performance computing and advanced network-on-chip, as well as other emerging technologies such as lab-on-chip sensors, with relevant applications in areas from medicine and biotechnology to aerospace. These demanding applications will require novel features, such as dynamically reconfigurable light pathways, obtained by properly harnessing on-chip optical radiation. In this paper, we introduce a broadband, high directivity (>150), low loss and reconfigurable silicon photonics nanoantenna that fully enables on-chip radiation control. We propose the use of these nanoantennas as versatile building blocks to develop wireless (unguided) silicon photonic devices, which considerably enhance the range of achievable integrated photonic functionalities. As examples of applications, we demonstrate 160 Gbit s−1 data transmission over mm-scale wireless interconnects, a compact low-crosstalk 12-port crossing and electrically reconfigurable pathways via optical beam steering. Moreover, the realization of a flow micro-cytometer for particle characterization demonstrates the smart system integration potential of our approach as lab-on-chip devices.

The performance of optical devices relying in vanadium dioxide (VO) technology compatible with the silicon platform depends on the polarization of light and VO properties. In this work, optical switching in hybrid VO/Si waveguides thermally triggered by lateral microheaters is achieved with insertion losses below 1 dB and extinction ratios above 20 dB in a broad bandwidth larger than 30 nm. The optical switching response has been optimized for TE and TM polarizations by using a homogeneous and a granular VO layer, respectively, with a small impact on the electrical power consumption. The stability and reversibility between switching states showing the possibility of bistable performance is also demonstrated.

Vanadium dioxide (VO(2)) is a metal-insulator transition (MIT) oxide recently used in plasmonics, metamaterials, and reconfigurable photonics. Because of the MIT, VO(2)shows great change in its refractive index allowing for ultra-compact devices with low power consumption. We theoretically demonstrate a transverse electric (TE) and a transverse magnetic (TM) pass polarizer with an ultra-compact length of only 1 μm and tunable using the MIT of the VO₂. During the insulating phase, both devices exhibit insertion losses below 2 dB at 1550 nm. Changing to the metallic phase, the unwanted polarization is attenuated above 15 dB while insertion losses are kept below 3 dB. Broadband operation over a range of 60 nm is also achieved.

A tunable transverse electric (TE) pass polarizer is demonstrated based on hybrid vanadium dioxide/silicon (VO/Si) technology. The 20-μm-long TE pass polarizer exploits the phase transition of the active VO material to control the rejection of the unwanted transverse magnetic (TM) polarization. The device features insertion losses below 1 dB at static conditions and insertion losses of 5.5 dB and an attenuation of TM polarization of 19 dB in the active state for a wavelength range between 1540 nm and 1570 nm. To the best of our knowledge, this is the first time that tunable polarizers compatible with Si photonics are demonstrated.

Mach-Zehnder interferometer (MZI) structures are widely used as optical switches in photonic integrated circuits. However, power consumption is still the key parameter to make such devices practical in the silicon platform, particularly for those based on the thermo-optic effect. A new approach to significantly decrease the power consumption of a silicon switch based on an asymmetric MZI, together with an optimum selection of the operation wavelengths, is proposed. A power consumption reduction up to 50% is experimentally demonstrated in agreement with simulation results.