An apparatus includes a dispersive-collimating element, a Faraday material apparatus and a focusing-dispersive element. The dispersive-collimating element assigns each beam wavelength to a particular spatial position. The beams are parallel one to the other. The Faraday material apparatus provides a polarization rotation independently for each wavelength, and the focusing-dispersive element recombines the different wavelengths into one single beam.

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.

An optical isolator device with minimized polarization mode dispersion includes a first polarization splitter/combiner, a non-reciprocal polarization rotator and a second polarization splitter/combiner. Only forward propagation of light is allowed to propagate in the device, with backward optical signal blocked due to non-reciprocal polarization rotation. The optical paths of o-ray and e-ray are arranged to achieve equal optical path lengths, which makes polarization mode dispersion minimal to nonexistent. When symmetrically configured, both polarization mode dispersion (PMD) and polarization dependent loss (PDL) become zero in principle.

A time-varying optical metasurface, comprising a plurality of modulated nano-antennas configured to vary dynamically over time. The metasurface may be implemented as part of an optical isolator, wherein the time-varying metasurface provides uni-directional light flow. The metasurface allows the breakage of Lorentz reciprocity in time-reversal. The metasurface may operate in a transmission mode or a reflection mode.

A miniaturized optical circulator includes: two polarized beam splitters and a 45-degree Faraday rotator, wherein an optical signal of a first optical path is input from a common terminal and is separated into a first polarization component and a second polarization component by a first polarized beam splitter, the first polarization component passes through the 45-degree Faraday rotator, reached a second polarized beam splitter and is reflected back, and passes through the 45-degree Faraday rotator and the first polarized beam, and reached a receiving terminal; the second polarization component under goes one reflection of the first polarization beam splitter subsequent to being separated, and reaches the receiving terminal; the optical signal of a second optical path is input, passes through the second polarized beam splitter, the 45-degree Faraday rotator, and the polarized beam splitter, and is output by the common terminal.

A photonic integrated circulator can be fabricated by including a plurality of polarizing beam splitters and optical polarization rotators such that two copies of the optical signal are output at a receiver in substantially aligned polarization states. The circulator can be used for facilitating bi-directional communications between photonic integrated circuit devices, which are inherently polarization sensitive, while reducing signal loss.

To a co-precipitating aqueous solution, aqueous solutions containing (a) Tb ions, (b) at least one other rare earth ions selected from the group consisting of Y ions and lanthanoid rare earth ions (excluding Tb ions), (c) Al ions and (d) Sc ions are added; the resulting solution is stirred at a liquid temperature of 50° C. or less to induce a co-precipitate of the components (a), (b), (c) and (d); the co-precipitate is filtered, heated and dehydrated; and the co-precipitate is fired thereafter at from 1,000° C. to 1,300° C., thereby forming a sinterable garnet-type complex oxide powder.

An optical circulator and an optical module are provided. The optical circulator includes a first polarization beam splitter member having a common optical port, a second polarization beam splitter member having an emittance optical port and at least two receiving optical ports, and a first polarization adjustment member. The two receiving optical ports respectively receive two linearly polarized light beams. The two linearly polarized light beams respectively pass through the second polarization beam splitter member, and sequentially pass through the first polarization adjustment member and the first polarization beam splitter member to be combined into a first combined light beam for being output from the common optical port. The common optical port receives a compound optical signal that passes through the first polarization beam splitter member to be split into another two linearly polarized light beams that are combined into a second combined light beam for being output.

An additive manufacturing apparatus including an energy source configured for transmitting a laser, a build plate configured to have a powder configured to be heated by the laser for additive manufacturing, at least one mirror positioned between the energy source and the build plate, the at least one mirror configured to direct the laser from the energy source to the build plate, and an optical isolator configured to reduce energy bounce back into the energy source.

An optical isolator includes a Faraday rotator including a trivalent ion exchange TAG (terbium-aluminum garnet), and arranged around the Faraday rotator, a central hollow magnet and a first and a second hollow magnet units arranged to sandwich the central hollow magnet in an optical axis direction. A magnetic flux density B [T] in the Faraday rotator and an optical path length L [mm] where the Faraday rotator is arranged satisfy

0<B  (1) and

14.0≤L≤24.0  (2).

The optical isolator, compared with a conventional Faraday rotator such as a terbium-gallium garnet (TGG) crystal, contributes to reduction of a thermal lensing effect, being a pending problem, in a high-output fiber laser.