In this paper we propose a novel hybrid optical plasmonic Vivaldi antenna for operation in the standard C telecommunication band for wavelengths in the 1550 nm range. The antenna is fed by a silicon waveguide and is designed to have high gain and large bandwidth. The shape of the radiation pattern, with a main lobe along the antenna axis, makes this antenna suitable for point-to-point connections for inter- or intra-chip optical communications. Direct port-to-port short links for different connection distances and in a homogeneous environment have also been simulated to verify, by comparing the results of a full-wave simulation with the Friis transmission equation, the correctness of the antenna parameters obtained via near-to-far field transformation.

In this paper, we propose a broadband silicon Mach-Zehnder switch (MZS) for wavelength division multiplexing applications on photonic networks on chip. The proposed reconfigurable switch is based on a single-stage three-waveguide interferometric configuration in which the phase shift is achieved via a p-i-n diode. The device is analyzed by the coupled-mode theory and by the finite-difference beam propagation method. The proposed configuration leads to a considerable increase in the bandwidth with respect to the conventional MZS. For example, the two-waveguide MZS with a gap g=0.30 μm between the two coupled waveguides exhibits bandwidth Δλ = 60 nm, crosstalk CT = - 15 dB, and insertion loss IL = 1.1 dB. Conversely, a bandwidth Δλ = 115 nm is achieved for the three-waveguide configuration to parity of the other parameters.

In this paper, we propose an optical 1 × 2 passive wavelength router (λ-router), based on photonic crystal ring resonators. The router, as basic building block to be assembled into higher order routing matrices, exploits a broadband crossing between two photonic crystal waveguides and a photonic crystal ring resonator. Moreover, we analyze the behavior of a 4 × 4 λ-router configuration obtained by assembling eight 1 × 2 routers. The design criteria are pointed out, and the numerical results, obtained by the finite-difference time-domain and the plane-wave expansion methods, are reported. The 4 × 4 λ-router has a footprint of 30 μm × 30 μm, and it is capable of connecting four transmitters with four receivers with a maximum crosstalk between the ports equal to -13.9 dB.

In this paper we report the design of a device allowing on-chip optical wireless interconnections, based on transmitting and receiving Optical Phased Arrays (OPA). The proposed device aims at realizing high-bandwidth and power-efficient reconfigurable connections between multiple nodes, e.g. chiplets stacked onto a common silicon interposer in 2.5D manycore systems. The communication through an optical wireless switch is a completely novel approach to overcome the bottleneck of wired communication and to provide flexibility in the network topology configuration. We report the OPA design criteria as well as the results of three-dimensional Finite Difference Time Domain (FDTD) simulations. We exploit the in-plane radiation of simple taper antennas to implement 1×N and N × N switching matrices. The effect of the multipath propagation in the on-chip multi-layered medium is also taken into account.

A notch filter based on an index confined photonic band gap waveguide is proposed. The dropping of an electromagnetic wave having a specific wavelength is obtained by opportunely designing a periodically corrugated overlay. The selective filtering properties of the proposed structure are identified by using a computer code based on the bidirectional beam propagation method with the aid of the method of lines. The optimized design of a notch filter, characterized by a full-width half-maximum (FWHM) bandwidth of 2 nm, is given. The tunability is reached by exploiting the electroclinic effect of smectic-A * liquid crystals.

Optical technology applied to on-chip wireless communication is particularly promising to overcome the performance limitations of the state-of-the-art networks on-chip. A key enabling component for such applications is the plasmonic antenna coupled to conventional silicon waveguides, which can guarantee full compatibility with standard optical circuitry. In this paper, we propose an antenna array configuration based on tilted plasmonic Vivaldi antennas coupled to a silicon waveguide. The details of the single antenna and of the array design are reported. The radiation characteristics of the array are suitable for on-chip point-to-point communication, i.e. in-plane maximum gain of 14.70 dB for an array with five antennas. The array exploits a travelling wave feeding scheme and, therefore, is compact in size (about 3.5 µm × 8.7 µm ).