Luis Sanchez

Ultra-compact TE and TM pass polarizers based on vanadium dioxide on silicon

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.

Low-Power Operation in a Silicon Switch Based on an Asymmetric Mach–Zehnder Interferometer

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.

On-chip wireless silicon photonics: from reconfigurable interconnects to lab-on-chip devices

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 160u2009Gbitu2009s−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.

Analysis and Design Optimization of a Hybrid VO 2 /Silicon2

The metal-to-insulator transition (MIT) property of vanadium dioxide (VO2) has recently been used in several application fields such as plasmonics, sensing, metamaterials, and optical modulation. Due to the MIT nature, VO2 allows a huge change in its complex refractive index that can be electrooptically controlled. In this paper, the analysis and design optimization of a 2 × 2 microring switch based on a hybrid VO2/silicon waveguide structure is addressed. Switching is achieved by exploiting the change in both absorption loss and phase shift that occurs in VO2 when changing from the insulating to the metallic state. The device is optimized to minimize insertion losses and crosstalk. An active length of only μm is required to achieve a data throughput rate higher than 500 Gb/s at a single optical wavelength.

\times

Two electronics subjects are taught in the Bachelors Degree in Aerospace Engineering at the School of Design Engineering (ETSID) of the Polytechnic University of Valencia (UPV). “Electronics Engineering” in which the fundamental of electronics are studied and “Electronics Technology” in which students apply the knowledge acquired in the previous one. The teaching methodology employed in this subject is the project based learning by means of the design and implementation of electronic projects related with the aeronautical engineering.

2 Microring Switch

A teaching experience with a high academic performance students group of Bachelors Degree in Industrial Electronics and Automation Engineering of Universitat Politècnica de Valencia (UPV) is described in this paper. The Digital Electronic subject has been imparted in this group using both standard integrated circuits as hardware description language (HDL). There is currently no unanimity over teaching the digital electronic bases from a traditional point of view or using the HDLs. Authors have wanted to validate the use of these languages not as implementation tools but as support to understand the concepts of digital systems.

Discovering electronics to aerospace engineers

A lateral displaced microheater is demonstrated for switching across the VO2 phase transition in ultra-short hybrid VO2/Si waveguides for both TE and TM light polarizations. Simulation and experimental results are obtained showing a very good agreement with a switching electrical power of around 10mW.

Using hardware description languages in a basic subject of Digital Electronic: Adaptation to high academic performance group

The influence of an external resistance on the performance of VO2 nanogap junctions is analyzed and experimentally characterized. The current-voltage response shows the reversible metal-insulator transition typical of VO2 based devices. When reaching the metallic state, the current through the VO2 junction is abruptly increased, which may result in electrical contact damage. Therefore, an external resistance in series with the VO2 junction is usually employed to limit the maximum current through the device. Our results indicate that the external resistance plays a key role in the switching power consumption showing an optimum value, which depends on the dimensions of the VO2 junction. In such a way, power consumption reductions up to 90% have been demonstrated by selecting the optimum external resistance value.

Thermo-optical switching in hybrid VO 2 /Sİ waveguides by lateral displaced microheaters

Silicon-photonic 2×2 electro-optical switching elements and modulators based on the carrier depletion mechanism using both dual-resonator and MZI layout configurations have been developed. The passive photonic structures were developed and optimized using a fast design-fabrication-characterization cycle. The main objective is to deliver smallfootprint, low-loss and low-energy silicon photonic electro-optical switching elements and modulators equipped with standard input-output grating couplers and radio-frequency electrical contact tips to allow their characterization in highspeed probe-station setups. The insertion losses, crosstalk, power consumption and BER performance will be addressed for each electro-optical structure. The fabrication steps, including low loss waveguide patterning, pn junction and low resistive ohmic contact formation have been optimized to produce high performance devices with relaxed fabrication tolerances, employing both optical and electron-beam lithography.

Impact of the external resistance on the switching power consumption in VO2 nano gap junctions

A novel method to significantly decrease power consumption in a silicon switch based on an asymmetric Mach-Zehnder interferometer (MZI) structure is proposed and experimentally demonstrated. A radical power consumption reduction up to 50% is achieved for switching digital data at bit rates from 10 to 30Gbps with respect to a conventional switch based on a symmetric MZI. Furthermore, the broadband performance of the proposed silicon MZI comb switch is also demonstrated by transmitting a 120 Gbps DWDM data stream.