CN-121986452-A - Optical transceiver with optical spectrum interleaving

Abstract

Wavelength Division Multiplexing (WDM) transceivers configured to support fast bi-directional communications over optical channels are described herein. An optical transceiver includes a transmitter, a receiver, an input/output (I/O) port, and an optical interleaver. The transmitter includes a first bus waveguide and a plurality of optical modulators coupled to the first bus waveguide, each optical modulator of the plurality of optical modulators resonating at a respective wavelength in the first set of wavelengths. The receiver includes a second bus waveguide and a plurality of optical filters coupled to the second bus waveguide, each of the plurality of optical filters resonating at a respective wavelength in the second set of wavelengths. The (I/O) port is coupled to an optical channel. The optical interleaver is configured to selectively couple light having wavelengths in the first set of wavelengths from the first bus waveguide to the I/O port and to selectively couple light having wavelengths in the second set of wavelengths from the I/O port to the second bus waveguide.

Inventors

• K.LIU
• N c harris
• S. A. Srinivasan
• GREENWALD ERIC
• SHAH BHRANTI
• S. Thain
• J. ROSENBERG
• N. KUMAR
• Anthony Copa
• C. Dolta Quinones
• S. Klinger
• D. Bunandar

Assignees

• 光物质公司

Dates

Publication Date

20260505

Application Date

20240925

Priority Date

20230927

Claims (20)

1. 1. An optical transceiver, comprising: a transmitter comprising a first bus waveguide and a plurality of optical modulators coupled to the first bus waveguide, each optical modulator of the plurality of optical modulators resonating at a respective wavelength in a first set of wavelengths; a receiver comprising a second bus waveguide and a plurality of optical filters coupled to the second bus waveguide, each optical filter of the plurality of optical filters resonating at a respective wavelength in a second set of wavelengths; An input/output (I/O) port configured to be coupled to an optical channel, wherein the I/O port forms a portion of a transmit path coupling the transmitter to the optical channel when the optical channel is coupled to the I/O port, and wherein the I/O port forms a portion of a receive path coupling the receiver to the optical channel when the optical channel is coupled to the I/O port, and An optical interleaver is provided with a plurality of optical filters, the optical interleaver is configured to: Selectively coupling light having a carrier wavelength in the first set of wavelengths from the first bus waveguide to the I/O port, and Light having a carrier wavelength in the second set of wavelengths is selectively coupled from the I/O port to the second bus waveguide.
2. 2. The optical transceiver of claim 1, wherein the optical interleaver comprises a mach-zehnder interferometer (MZI) having a first coupler coupled to both the first bus waveguide and the second bus waveguide and a second coupler coupled to the I/O port.
3. 3. The optical transceiver of claim 2, wherein the mach-zehnder interferometer is a multi-stage MZI, wherein the multi-stage MZI further comprises a third coupler, wherein the third coupler is coupled to both a first stage of the multi-stage MZI and a second stage of the multi-stage MZI.
4. 4. The optical transceiver of claim 3, wherein a first stage of the multi-stage MZI defines a first optical path length difference and a second stage of the multi-stage MZI defines a second optical path length difference different from the first optical path length difference.
5. 5. The optical transceiver of claim 4, wherein the first optical path length difference is about twice the second optical path length difference.
6. 6. The optical transceiver of claim 1, wherein the optical interleaver comprises at least one interferometer selected from the group consisting of a multimode interferometer (MMI) device, an Arrayed Waveguide Grating (AWG), and an asymmetric mach-zehnder interferometer (MZI).
7. 7. The optical transceiver of claim 1, wherein the carrier wavelengths of the first set of wavelengths are contiguous and the carrier wavelengths of the second set of wavelengths are contiguous.
8. 8. The optical transceiver of claim 7, wherein the optical interleaver comprises a first optical arm and a second optical arm, wherein an optical path length difference between the first optical arm and the second optical arm is configured to cause the optical interleaver to: selectively coupling light having consecutive carrier wavelengths in the first set of wavelengths from the first bus waveguide to the I/O port, and Light having consecutive carrier wavelengths in the second set of wavelengths is selectively coupled from the I/O port to the second bus waveguide.
9. 9. The optical transceiver of claim 1, wherein carrier wavelengths of the first set of wavelengths alternate with carrier wavelengths of the second set of wavelengths.
10. 10. The optical transceiver of claim 9, wherein the optical interleaver comprises a first optical arm and a second optical arm, wherein an optical path length difference between the first optical arm and the second optical arm is configured to cause the optical interleaver to: selectively coupling light having alternating carrier wavelengths in the first set of wavelengths from the first bus waveguide to the I/O port, and Light having alternating carrier wavelengths in the second set of wavelengths is selectively coupled from the I/O port to the second bus waveguide.
11. 11. The optical transceiver of claim 1, further comprising an optical polarization controller coupled between the I/O port and the optical interleaver, wherein when the optical channel is coupled to the I/O port, the optical polarization controller is configured to provide a pair of output Transverse Electric (TE) modes to the optical interleaver upon receiving an input TE mode and an input Transverse Magnetic (TM) mode from the optical channel.
12. 12. The optical transceiver of claim 1, wherein the transmitter, the receiver, the I/O port, and the optical interleaver are integrated on a common substrate, and wherein the I/O port comprises a grating coupler or an edge coupler.
13. 13. The optical transceiver of claim 1, wherein carrier wavelengths in the first set of wavelengths are spaced apart from each other by a spectral separation in the range of 1.72 nm to 2.86 nm and carrier wavelengths in the second set of wavelengths are spaced apart from each other by a spectral separation in the range of 1.72 nm to 2.86 nm.
14. 14. The optical transceiver of claim 13, wherein the plurality of optical modulators have a Free Spectral Range (FSR) of less than 11.44 nm.
15. 15. An optical transceiver, comprising: a launch bus waveguide and a plurality of optical resonant modulators coupled to the launch bus waveguide; a receive bus waveguide and a plurality of optical resonant filters coupled to the receive bus waveguide; An asymmetric mach-zehnder interferometer (MZI) having a first end and a second end opposite the first end, wherein the first end comprises a first waveguide coupled to the transmit bus waveguide and a second waveguide coupled to the receive bus waveguide, and wherein the second end comprises a third waveguide.
16. 16. The optical transceiver of claim 15, wherein the asymmetric MZI comprises a plurality of stages defining a plurality of optical path length differences, wherein the optical path length differences are configured to cause the asymmetric MZI to: Selectively coupling light having a continuous carrier wavelength in a first band from the first waveguide to the third waveguide, and Light having a continuous carrier wavelength in a second wavelength band is selectively coupled from the third waveguide to the second waveguide.
17. 17. The optical transceiver of claim 15, wherein the asymmetric MZI comprises a plurality of stages defining a plurality of optical path length differences, wherein the optical path length differences are configured to cause the asymmetric MZI to: selectively coupling light having a carrier wavelength of a first set of wavelengths from the first waveguide to the third waveguide, and Selectively coupling light having a carrier wavelength in a second set of wavelengths from the third waveguide to the second waveguide, Wherein the carrier wavelengths of the first set of wavelengths alternate with the carrier wavelengths of the second set of wavelengths.
18. 18. The optical transceiver of claim 17, wherein the first carrier wavelengths of the first set of wavelengths and the second carrier wavelengths of the second set of wavelengths adjacent to each other are spaced apart from each other by a spectral separation in the range of 1.14 nm to 2.28 nm.
19. 19. The optical transceiver of claim 15, further comprising an optical polarization controller coupled to a third waveguide of the asymmetric MZI, wherein the optical polarization controller is configured to provide a pair of output Transverse Electric (TE) modes to the asymmetric MZI upon receiving the input Transverse Magnetic (TM) modes.
20. 20. The optical transceiver of claim 15, wherein the asymmetric MZI further comprises: a phase shifter positioned between the first end and the second end, wherein the second end of the asymmetric MZI further comprises a fourth waveguide; a photodetector coupled to the fourth waveguide, and A controller configured to receive photocurrent generated by the photodetector and to control the phase shifter based on the photocurrent so as to minimize an amount of optical power coupled to the fourth waveguide.

Description

Optical transceiver with optical spectrum interleaving Cross Reference to Related Applications The present application enjoys the benefits of U.S. provisional patent application serial No. 63/585,923, entitled "PHOTONIC INTERCONNECT (photonic interconnect)", attorney docket No. L0858.70084US00, filed on 9, month 19 of 2024, entitled "PHOTONIC DEVICES WITH INTERLEAVED OPTICAL CHANNELS AND POLARIZATION CONTROL (photonic device with interleaved OPTICAL channels and polarization control)", attorney docket No. L0858.70097US00, in accordance with the 35 u.s.c. ≡119 (e) requirements. Background An optical transceiver is a device that uses optical signals (typically through fiber optic cables) to transmit and receive data. Optical transceivers play a critical role in telecommunications and data communication networks to convert electrical signals into optical signals for transmission and then convert the optical signals back into electrical signals at the receiving end. Wavelength division multiplexing (WAVELENGTH DIVISION MULTIPLEXING, WDM) is a technique used in optical communications to simultaneously transmit multiple signals over a single optical fiber. WDM achieves this by using different wavelengths (colors) of light for each signal, allowing for efficient use of the fiber bandwidth and significantly improving data carrying capacity. Ring resonator based WDM transmitters are an advanced component in optical communications for implementing efficient WDM. These devices utilize the characteristics of ring resonators to filter and control light of specific wavelengths, allowing for precise manipulation and routing of optical signals in WDM systems. When light of multiple wavelengths is introduced into the waveguide, the ring resonator selectively couples wavelengths matching its resonant wavelength. This enables it to act as a filter, allowing only the desired wavelength to pass or be guided into (drop) adjacent waveguides. Disclosure of Invention Some embodiments relate to an optical transceiver including a transmitter including a first bus waveguide and a plurality of optical modulators coupled to the first bus waveguide, each of the plurality of optical modulators resonating at a respective wavelength in a first set of wavelengths, a receiver including a second bus waveguide and a plurality of optical filters coupled to the second bus waveguide, each of the plurality of optical filters resonating at a respective wavelength in the second set of wavelengths, an input/output (I/O) port configured to be coupled to an optical channel, wherein the I/O port forms a portion of a transmit path coupling the transmitter to the optical channel when the optical channel is coupled to the I/O port, and wherein the I/O port forms a portion of a receive path coupling the receiver to the optical channel when the optical channel is coupled to the I/O port, and an optical interleaver configured to selectively couple light having a carrier wavelength in the first set of wavelengths from the first bus to the I/O port and selectively couple light having a carrier wavelength in the first set of wavelengths from the first bus to the I/O port to the carrier having the second set of wavelengths. In some embodiments, the optical interleaver includes a Mach-Zehnder interferometer (Mach Zehnder interferometer, MZI) having a first coupler coupled to both the first bus waveguide and the second bus waveguide and a second coupler coupled to the I/O port. In some embodiments, the mach-zehnder interferometer is a multi-stage MZI, wherein the multi-stage MZI further comprises a third coupler, wherein the third coupler is coupled to both the first stage of the multi-stage MZI and the second stage of the multi-stage MZI. In some embodiments, a first stage of the multi-stage MZI defines a first optical path length difference and a second stage of the multi-stage MZI defines a second optical path length difference different from the first optical path length difference. In some embodiments, the first optical path length difference is about twice the second optical path length difference. In some embodiments, the optical interleaver comprises at least one interferometer selected from the group consisting of a multimode interferometer (MMI) device, an Arrayed Waveguide Grating (AWG), and an asymmetric mach-zehnder interferometer (MZI). In some embodiments, the carrier wavelengths of the first set of wavelengths are contiguous and the carrier wavelengths of the second set of wavelengths are contiguous. In some embodiments, the optical interleaver includes a first optical arm and a second optical arm, wherein an optical path length difference between the first optical arm and the second optical arm is configured to cause the optical interleaver to selectively couple light having consecutive carrier wavelengths in the first set of wavelengths from the first bus waveguide to the I/O port and to selectively couple light having consecutive carrier wavelengt