Abstract:
An optoelectronic device (10) includes an input waveguide structure (14) that receives an input optical signal. A GeSi/Si waveguide structure (12) receives from the input waveguide the input optical signal and performs selective optoelectronic operations on the input optical signal. The GeSi/Si waveguide structure outputs an optical or electrical output signal associated with the selective optoelectronic operations performed on the input optical signal . An output waveguide (16) structure receives the output optical signal from the GeSi/Si waveguide structure and provides the optical output signal for further processing.
Abstract:
The invention relates to an optoelectronic device for generating a frequency comb comprising a laser source (2), a ring microresonator (3) comprising a resonant ring (20) made of a third order optically non-linear material with abnormal dispersion regime. It also comprises a spectral tuning device comprising a junction guide (30) coupled to the resonant ring, electrical biasing means (40) adapted to apply an electrical voltage to the junction, and a control unit (42) adapted to modify the value of the electrical voltage until at least one dissipative temporal soliton is formed in the resonant ring.
Abstract:
A semiconductor optical waveguide device includes a substrate having a first area and a second area, and first, second, and semiconductor mesas on the substrate. The first semiconductor mesa includes a cladding layer and a first mesa portion on the second area, the first mesa portion including first and second portions. The second semiconductor mesa includes an intermediate layer, a first core layer, and first and second mesa portions on the first and second area, respectively. The third semiconductor mesa includes a second core layer, and first and second mesa portions having a greater width than that of the second semiconductor mesa. The first portion of the first semiconductor mesa has a substantially the same width as the second mesa portion of the second semiconductor mesa. The first core layer is optically coupled to the second core layer through the intermediate layer disposed between the first and second core layers.
Abstract:
An optical amplifier includes an optical gain fiber into which signal light and pump light are input and at least one relative phase shifter is inserted. Preferably, the relative phase shifter is inserted so that the relative phase in the lengthwise direction of the optical gain fiber falls within a predetermined range containing 0.5 Π. Preferably, the optical gain fiber is a highly non-linear optical fiber having a non-linearity constant of at least 10/W/km. Preferably, the dispersion of the optical gain fiber is within the range from −1 ps/nm/km to 1 ps/nm/km in an amplification band. Preferably, the absolute value of the dispersion slope of the optical gain fiber at a zero dispersion wavelength is no greater than 0.05 ps/nm2/km.
Abstract:
When an output instruction is input to a control unit, the control unit controls a seed laser light source and a pumping light source to be either in a pre-pumped state or in an output state. In the pre-pumped state, the pumping light source outputs, for a predetermined period, pumping light with an intensity determined based on the duration of the period of time from when the output state prior to the input of the output instruction to the control unit comes to an end till when the output instruction is input to the control unit. In the output state, to cause the output unit to output laser light, the seed laser light source outputs laser light, and the pumping light source outputs pumping light.
Abstract:
When an output instruction is input to a control unit, the control unit controls a seed laser light source and a pumping light source to be either in a pre-pumped state or in an output state. In the pre-pumped state, the pumping light source outputs, for a predetermined period, pumping light with an intensity determined based on the duration of the period of time from when the output state prior to the input of the output instruction to the control unit comes to an end till when the output instruction is input to the control unit. In the output state, to cause the output unit to output laser light, the seed laser light source outputs laser light, and the pumping light source outputs pumping light.
Abstract:
A fiber optical attenuator utilizing the cut-off phenomenon for single mode propagation of an optical wave down a single mode fiber, comprising an element such as a pixelated liquid crystal element, capable of spatially changing the phase across the cross section of an input optical signal. Such a spatial phase change is equivalent to a change in the mode structure of the propagating wave. The signal propagating in the single mode output fiber is attenuated in accordance with the extent to which higher order modes are mixed into the low order mode originally present. When the mode is completely transformed to higher order modes, the wave is effectively completely blocked from entering the output single-mode fiber, and the attenuation is high. The level of attenuation is determined by the fraction of the wave which is converted to modes other than the lowest order mode, and is thus controllable by the voltage applied to the pixels of the liquid crystal element.
Abstract:
A fiber laser device capable of restraining variations of the rise time of output laser light while shortening the rise time of the output laser light is provided. A fiber laser device (100) includes a seed laser light source (10), a pumping light source (20), an amplification optical fiber (30), a control unit (60), and an output instructing unit (65). When an output instruction is input to the control unit (60), the control unit (60) controls the seed laser light source (10) and the pumping light source (20) to be either in a pre-pumped state or in an output state. In the pre-pumped state, the pumping light source (20) outputs, for a predetermined period, pumping light with an intensity determined based on the duration of the period of time from when the output state prior to the input of the output instruction to the control unit (60) comes to an end till when the output instruction is input to the control unit (60). In the output state, to cause the output unit (50) to output laser light, the seed laser light source (10) outputs laser light, and the pumping light source (20) outputs pumping light.