An optical coupling device can couple incident light from a fiber into waveguides, but can reduce the coupling of return light from the waveguides into the fiber. A Faraday rotator layer can rotate by forty-five degrees, with a first handedness, respective planes of polarization of incident beams, and can rotate by forty-five degrees, with a second handedness opposite the first handedness, respective planes of polarization of return beams. A redirection layer can include at least one grating coupler that can redirect an incident beam of one polarization so that the redirected path extends within the redirection layer toward a first waveguide, and can redirect an incident beam of an opposite polarization so that the redirected path extends within the redirection layer toward a second waveguide. An optional birefringent layer can spatially separate incident beam having different polarizations, so that two single-polarization grating couplers can be used.

Embodiments disclosed herein include photonics package with Faraday rotators to improve efficiency. In an embodiment, a photonics package comprises a package substrate and a compute die over the package substrate. In an embodiment, the photonics package further comprises a photonics die over the package substrate. In an embodiment, the compute die is communicatively coupled to the photonics die by a bridge in the package substrate. In an embodiment, the photonics package further comprises an integrated heat spreader (IHS) over the package substrate, and a Faraday rotator passing through the IHS and optically coupled to the photonics die.

Embodiments disclosed herein include optical systems with Faraday rotators in order to enhance efficiency. In an embodiment, a photonics package comprises an interposer and a patch over the interposer. In an embodiment, the patch overhangs an edge of the interposer. In an embodiment, the photonics package further comprises a photonics die on the patch and a Faraday rotator passing through a thickness of the patch. In an embodiment, the Faraday rotator is below the photonics die.

An apparatus includes a substrate. A laser is formed on a non-self supporting structure and bonded to the substrate. A waveguide having a gap portion is deposited proximate the laser. The waveguide is configured to communicate light from the laser to a near-field transducer (NFT) that directs energy resulting from plasmonic excitation to a recording medium. An optical isolator is disposed over the gap portion.

In some implementations, an optical isolator core includes a Faraday rotator and a plurality of birefringent crystal plates. The plurality of birefringent crystal plates may include a first birefringent crystal plate to separate input light into light having a first polarization and light having a second polarization, and a second birefringent crystal plate to combine the light having the first polarization and the light having the second polarization in output light that is laterally displaced by the single stage optical isolator. The Faraday rotator may be provided between the first birefringent crystal plate and the second birefringent crystal plate. In some implementations, the plurality of birefringent crystal plates further include a third birefringent crystal plate provided between the Faraday rotator and the second birefringent crystal plate. Additionally, or alternatively, the optical isolator core may further include a half-wave plate arranged between the Faraday rotator and the first birefringent crystal plate.

An optical module of the present disclosure includes an optical element, a first optical component that is optically coupled to the optical element, a second optical component that is optically coupled to the first optical component, a receptacle to which an optical fiber that transmits the incident light to the second optical component is connected, a terminal unit that electrically outputs an output signal of the optical element to the outside, and a package that accommodates the optical element, the first optical component, and the second optical component and is provided with the receptacle on a first surface and the terminal unit on a second surface facing the first surface, wherein the wiring extends from the first surface side to the second surface side and electrically connects the second optical component and the terminal unit.

Methods and systems for a light source arrangement supporting direct coupling to a photonically enabled complementary metal-oxide semiconductor (CMOS) chip are disclosed. The arrangement may include a laser, a microlens, a turning mirror, reciprocal and/or non-reciprocal polarization rotators, and an optical bench. The laser may generate an optical signal that may be focused utilizing the microlens. The optical signal may be reflected at an angle defined by the turning mirror, and may be transmitted out of the light source arrangement to one or more grating couplers in the chip. The laser may include a feedback insensitive laser. The light source arrangement may include two electro-thermal interfaces between the optical bench, the laser, and a lid affixed to the optical bench. The turning mirror may be integrated in a lid affixed to the optical bench or may be integrated in the optical bench.

The invention describes an apparatus that implements efficient coupling between a photonic integrated circuit (PIC) and a second optical element such as a fiber or laser, while at the same time allowing for efficient polarization management and/or optical isolation. It enables the packaging of PICs with large single mode fiber counts and in- and out-coupling of light with arbitrary polarization. The apparatus comprises a glass interposer that contains at least one polarization selective element together with a pair of lenses transforming a beam profile between the 2nd optical element and a polarization selective coupler on the PIC. The invention also comprises a method for fabricating the apparatus based on a subassembly of building blocks that are manufactured using wafer-scale high-precision glass-molding and surface treatment(s) such as thin-film coating.

An apparatus includes multiple dual cladding waveguides each having a single-mode interior section that transports one of multiple outgoing optical signals and a multimode section at least partially surrounding the interior section that transports one of multiple incoming optical signals. Different outgoing signals have different polarizations, and different incoming signals have different polarizations. The apparatus also includes a polarization beamsplitter that combines the multiple outgoing signals to produce transmit optical signals and separates receive optical signals to produce the multiple incoming signals.

A system includes an optical transceiver configured to transmit and receive optical signals. The optical transceiver includes a Faraday rotator and a waveplate. The Faraday rotator and the waveplate are collectively configured to provide a relative polarization change between (i) light propagating in a first direction through the Faraday rotator and the waveplate and (ii) light propagating in a second direction opposite the first direction through the Faraday rotator and the waveplate. The waveplate may include a quarter waveplate or a half waveplate.