Abstract: A grating coupler is disclosed. The grating coupler comprises a grating formed in a waveguide formed in a silicon layer of a silicon on insulator photonic component. The grating has a series of sequentially arranged grating elements i, each comprising an alternating etched trench section having a length Le and an etch depth e, and an unetched tooth section having a length L0. Each grating element has a total length of ?i and a fill factor Fi. The fill factor Fi of each grating element varies across the grating coupler according to an apodization function dependent on the location of the grating element. The total length of each grating element ?i varies across the grating coupler such that the effective refractive index of each grating element causes the Bragg condition to be satisfied for all of the grating elements of the grating.

Abstract: Is disclosed a device for manipulating a particle immersed in a fluid, comprising a probe having a first end, a second end and a longitudinal axis. The probe receives a radiation from a light source and emits the radiation by means of the second end. The probe comprises: an optical guide structure suitable for receiving the radiation. The optical guide structure is configured so that: at the second end, the radiation has an optical intensity distribution with an intensity maximum placed at a non-zero distance from the longitudinal axis of the probe; and in the region of the intensity maximum, the radiation is reflected at the interface between the second end and the fluid and is emitted by the second end so that it converges in a convergence point, thus creating an equilibrium point. The probe further comprises perturbation optical means for perturbing the equilibrium point.

Abstract: It is disclosed an optical device for trapping a particle immersed in a fluid. The device of the invention comprises a light source and a probe for guiding and outputting the radiation received from the source. According to the invention, the guided radiation has an intensity distribution having intensity maximum placed at a non-zero distance from the probe longitudinal axis and having rotational symmetry about the longitudinal axis. Further, according to the invention, the intensity maximum is reflected at the interface between probe and fluid, and then it is output by the probe so that it creates a stable equilibrium point wherein the particle is trapped.

Abstract: An optical communication line of a communication system has a first processing station and an amplifying station. The line has a first optical connection having at least partially compensated accumulated dispersion and is placed between the first processing station and the amplifying station. A second optical connection having at least partially compensated accumulated dispersion is connected to the output of the amplifying station. Portions of optical fiber leaving the processing station and the amplifying station are associated to respective first order chromatic dispersions which are of opposite signs and have absolute values lower than or equal to 13 ps2/Km.

Abstract: An optical system having an optical fiber path suitable for propagating an optical signal at least in a first direction, and a plurality M of optical amplifiers disposed along the optical fiber path so as to divide the optical fiber path in N spans of optical fiber. The spans of optical fiber all have substantially a length Lamp and have at least one transmission optical fiber having an effective length Leff. An optical phase conjugation device is associated to one of the amplifiers of the plurality of amplifiers and is disposed in combination with a dispersion compensator. The compensator is disposed upstream from the amplifier associated to the optical phase conjugation device and is adapted for introducing an accumulated dispersion such as to substantially compensate the dispersion accumulated in a portion having a length (Lamp?Leff) of the span immediately upstream from the amplifier associated to the optical phase conjugation device.

Abstract: An optical communication line of a communication system has a first processing station and an amplifying station. The line has a first optical connection having at least partially compensated accumulated dispersion and is placed between the first processing station and the amplifying station. A second optical connection having at least partially compensated accumulated dispersion is connected to the output of the amplifying station. Portions of optical fiber leaving the processing station and the amplifying station are associated to respective first order chromatic dispersions which are of opposite signs and have absolute values lower than or equal to 13 ps2/Km.

Abstract: An optical system has an optical fiber path suitable for propagating an optical signal at least in a first direction, and a plurality of optical line amplifiers disposed along the optical fiber path so as to divide the optical fiber path in spans of optical fiber. The spans of optical fiber have at least one transmission optical fiber having an effective length Leff. An optical phase conjugation device is associated to one of the amplifiers of the plurality of amplifiers, and is disposed in combination with an optical fiber length having the same sign of dispersion of the transmission optical fiber and a higher dispersion coefficient at a wavelength of the optical signal. The additional accumulated dispersion introduced by the optical fiber length is nearly equal to the dispersion accumulated in an effective length Leff of transmission fiber. A further optical amplifier is associated to the optical fiber length.

Abstract: An optical system having an optical fiber path suitable for propagating an optical signal at least in a first direction, and a plurality M of optical amplifiers disposed along the optical fiber path so as to divide the optical fiber path in N spans of optical fiber. The spans of optical fiber all have substantially a length Lamp and have at least one transmission optical fiber having an effective length Leff. An optical phase conjugation device is associated to one of the amplifiers of the plurality of amplifiers and is disposed in combination with a dispersion compensator. The compensator is disposed upstream from the amplifier associated to the optical phase conjugation device and is adapted for introducing an accumulated dispersion such as to substantially compensate the dispersion accumulated in a portion having a length (Lamp?Leff) of the span immediately upstream from the amplifier associated to the optical phase conjugation device.

Abstract: An optical system having an optical fiber path suitable for propagating an optical signal at least in a first direction, a plurality of optical gain modules disposed along the optical fiber path so as to divide the optical fiber path in N spans of optical fiber. Each span of optical fiber has at least one transmission optical fiber connected downstream from the optical gain modules. An optical phase conjugation device is disposed at a predetermined distance downstream from one of the optical gain modules.