Abstract: Methods, systems, and apparatus, including an optical receiver including an optical source, including a substrate; a laser provided on the substrate, the laser having first and second sides and outputting first light from the first side and second light from the second side, the first light output from the first side of the laser has a first power and the second light output from the second side has a second power; and a first modulator that receives the first light and a second modulator that receives the second light, such that the power of the first light at an input of the first modulator is substantially equal to the power of the second light at an input of the second modulator.

Abstract: Consistent with the present disclosure, a compact laser with extended tunability (CLET) is provided that includes multiple segments or sections, at least one of which is curved, bent or non-collinear with other segments, so that the CLET has a compact form factor either as a singular laser or when integrated with other devices. The term CLET, as used herein, refers to any of the laser configurations disclosed herein having mirrors and a bent, angled or curved part, portion or section between such mirrors. If bent, the bent portion is preferably oriented at an angle of at least 30 degrees relative to other portions of the CLET. Alternatively, the curve or bend portion may be distributed over different sections of the CLET over a series of arcs, for example. The waveguide extending between the mirrors is continuous, such that light propagating along the waveguide is not divided or split. The waveguide also constitutes a continuous waveguide path.

Abstract: Consistent with the present disclosure, a compact laser with extended tunability (CLET) is provided that includes multiple segments or sections, at least one of which is curved, bent or non-collinear with other segments, so that the CLET has a compact form factor either as a singular laser or when integrated with other devices. The term CLET, as used herein, refers to any of the laser configurations disclosed herein having mirrors and a bent, angled or curved part, portion or section between such mirrors. If bent, the bent portion is preferably oriented at an angle of at least 30 degrees relative to other portions of the CLET. Alternatively, the curve or bend portion may be distributed over different sections of the CLET over a series of arcs, for example. The waveguide extending between the mirrors is continuous, such that light propagating along the waveguide is not divided or split. The waveguide also constitutes a continuous waveguide path.

Abstract: A Raman pump may include a dual output laser configured to output two optical signals; a delay interferometer configured to delay a first of the two optical signals to decorrelate the two optical signals from each other; and a combiner configured to combine the delayed first of the two optical signals and a second of the two optical signals to provide a Raman amplification signal.

Abstract: A device may include a number of optical waveguides, each of which being spaced from one another. The optical waveguides may each include at least one curved section and widths of the curved sections of the optical waveguides may be selected to reduce polarization conversion of light traversing the birefringent optical waveguides.

Abstract: The present invention provides for a semiconductor laser having a narrow linewidth and low power consumption for optical communication applications. According to various embodiments of the invention, a semiconductor laser is provided which includes a grating layer comprising a plurality of segmented gratings, each including a non-grating portion and a grating portion. The segmented gratings are configured to enhance a fundamental mode of the semiconductor laser while sufficiently suppressing modes other than the fundamental mode, providing a narrow linewidth for example. The segmented gratings are also configured to provide an effective length longer than an actual length of the semiconductor laser, leading to smaller device areas and corresponding lower power consumption. A photonic integrated circuit is also provided which includes a plurality of semiconductor lasers, consistent with the present invention, as well as additional optical elements, all provided on a single substrate.

Abstract: A semiconductor optical amplifier module may include a beam splitter to split an optical signal into two polarization optical signals including a first polarization optical signal with a Transverse Magnetic (TM) polarization provided along a first path of two paths, and a second polarization optical signal with a Transverse Electric (TE) polarization provided along a second path of the two paths; a first rotator to rotate the TM polarization of the first polarization optical signal to TE polarization; a first semiconductor optical amplifier to amplify the rotated first polarization optical signal to output a first resultant optical signal; a second semiconductor optical amplifier to amplify the second polarization optical signal; and a second rotator to rotate the polarization of the amplified second polarization optical signal to output a second resultant optical signal; and a beam combiner to combine the first resultant optical signal and the second resultant optical signal.

Abstract: An optical device may include a substrate; an arrayed waveguide grating provided on the substrate and having first and second slabs; multiple first waveguides extending from the first slab, the multiple first waveguides may supply respective first optical signals to the first slab; multiple second waveguides extending from the second slab, the multiple second waveguides may supply respective second optical signals to the second slab; a third waveguide extending from the second slab, the third waveguide outputting a third optical signal from the second slab, the third optical signal including the first optical signals; a fourth waveguide extending from the first slab, the fourth waveguide may output a fourth optical signal from the first slab, the fourth optical signal including the second optical signals; and a first scattering device optically coupled to a portion of an edge of the first slab between the multiple first waveguides and the fourth waveguide.

Abstract: Consistent with the present disclosure, MZ drive signal electrodes may be provided relatively close to and parallel to one another, such that the underlying waveguide arms may also be provided close to and parallel to one another. As a result, common mode performance of an MZ modulator may be obtained. In one example, an electrode wiring configuration consistent with the present disclosure may permit a waveguide arm separation of 40 microns or less.

Abstract: A device may include a number of optical waveguides, each of which being spaced from one another. The optical waveguides may each include at least one curved section and widths of the curved sections of the optical waveguides may be selected to reduce polarization conversion of light traversing the birefringent optical waveguides.

Abstract: A Raman pump may include a dual output laser configured to output two optical signals; a delay interferometer configured to delay a first of the two optical signals to decorrelate the two optical signals from each other; and a combiner configured to combine the delayed first of the two optical signals and a second of the two optical signals to provide a Raman amplification signal.

Abstract: A semiconductor optical amplifier module may include a beam splitter to split an optical signal into two polarization optical signals including a first polarization optical signal with a Transverse Magnetic (TM) polarization provided along a first path of two paths, and a second polarization optical signal with a Transverse Electric (TE) polarization provided along a second path of the two paths; a first rotator to rotate the TM polarization of the first polarization optical signal to TE polarization; a first semiconductor optical amplifier to amplify the rotated first polarization optical signal to output a first resultant optical signal; a second semiconductor optical amplifier to amplify the second polarization optical signal; and a second rotator to rotate the polarization of the amplified second polarization optical signal to output a second resultant optical signal; and a beam combiner to combine the first resultant optical signal and the second resultant optical signal.

Abstract: The present invention provides a polarization converter, and a method for fabricating the same. The polarization converter includes a geometric shape which induces rotation of a polarization of an optical signal from a first polarization state to a second polarization state as the optical signal propagates along the polarization converter. The performance of the polarization converter is maintained in light of inconsistencies in fabrication processes resulting in improved manufacturability.

Abstract: Consistent with the present disclosure, both arms of an MZ interferometer are “double-folded” and are bent in at least two locations to define first and second acute inner angles. Accordingly, the arms of the MZ interferometer may have substantially the same length, and, further, the MZ interferometer has a more compact geometry. In one example, the arms parallel each other and have a serpentine shape, and, in a further embodiment, the arms parallel one another and have a Z-shape. Accordingly, since the temperature of a PIC upon which the MZ interferometer is provided does not vary significantly over such short distances, the temperatures of both arms is substantially the same.

Abstract: Consistent with the present disclosure, MZ drive signal electrodes may be provided relatively close to and parallel to one another, such that the underlying waveguide arms may also be provided close to and parallel to one another. As a result, common mode performance of an MZ modulator may be obtained. In one example, an electrode wiring configuration consistent with the present disclosure may permit a waveguide arm separation of 40 microns or less.

Abstract: A photonic integrated circuit (PIC) having multiple Mach-Zehnder (MZ) modulators with different lengths is provided. The modulator lengths are selected to provide optimal performance for each optical path provided on the PIC.

Abstract: Consistent with the present disclosure, a current blocking layer is provided between output waveguides carrying light to be sensed by the photodiodes in a balanced photodetector, and the photodiodes themselves. Preferably, the photodiodes are provided above the waveguides and sense light through evanescently coupling with the waveguides. In addition, the current blocking layer may include alternating p and n-type conductivity layers, such that, between adjacent ones of such layers, a reverse biased pn-junction is formed. The pn-junctions, therefore, limit the amount of current flowing from one photodiode of the balanced detector to the other, thereby improving performance.

Abstract: Consistent with the present disclosure, various optical components are preferably arranged on the surface of a semiconductor substrate such that light propagates in certain components at a direction that is perpendicular to a direction of propagation in other components in order to improve performance and component density.

Abstract: Consistent with the present disclosure, the number of passive waveguides in a PIC are reduced by directly connecting active components to one another. Accordingly, optical signals propagating in the PIC may experience less loss, and, thus, improved performance may be achieved. In addition, active components may be bent or curved in order to obtain a more compact layout with greater device density. Reduced manufacturing costs can therefore be realized.

Abstract: A modulator is disclosed that includes three arms between a splitter portion and a coupler portion. The modulator typically requires at most a ?/2 phase shift between constellation points. Accordingly, the modulator is more efficient and consumes less power.