Disclosed are a wavelength-selectable laser diode and an optical communication apparatus including the same. The wavelength-selectable laser diode includes a substrate, which includes a gain region, a tuning region spaced apart from the gain region, and a phase adjusting region between the tuning region and the gain region, a waveguide layer on the substrate, a clad layer on the waveguide layer, and gratings disposed on the substrate or the clad layer in the gain region and the tuning region.

A transmitter can include a laser operable to output an optical signal; a digital signal processor operable to receive user data and provide electrical signals based on the data; and a modulator operable to modulate the optical signal to provide optical subcarriers based on the electrical signals. A first one of the subcarriers carriers carries first TDMA encoded information and second TDMA encoded information, such that the first TDMA encoded information is indicative of a first portion of the data and is carried by the first one of the subcarriers during a first time slot, and the second TDMA encoded information is indicative of a second portion of the data and is carried by the first one of the subcarriers during a second time slot. The first TDMA encoded information is associated with a first node remote from the transmitter and the second TDMA encoded information is associated with a second node remote from the transmitter. A second one of the subcarriers carries third information that is not TDMA encoded, the third information being associated with a third node remote from the transmitter. A receiver and system also are described.

An optical fiber amplification apparatus is disclosed, including an optical receiving port, a first optical output port, a second optical output port, a gain medium, a pump laser, reflection films, and a transmission-reflection film. The pump laser activates a function of the gain medium to amplify an optical signal. A multiplexed optical signal including a first-waveband optical signal and a second-waveband optical signal is incident onto the gain medium. The reflection films enable the multiplexed optical signal to be reflected back and forth in the gain medium. After the first-waveband optical signal reaches a first target gain, the first-waveband optical signal is output from the gain medium to the first optical output port. The second-waveband optical signal is amplified in the gain medium. After the second-waveband optical signal reaches a second target gain, the second-waveband optical signal is output from the gain medium to the second optical output port.

An interconnect transceiver for transmitting and receiving optical signals, comprising an electronics module with a transceiver engine, and a photonics module with a laser source, a modulator, a photodetector to monitor the laser, one to receive an external optical signal, and a controller to operate the laser source and the laser source modulator, an electronic switch having two states is proposed. The first state is to allow monitoring of the modulated laser source by the transceiver engine, so as to acquire a reference set of operating parameters, and the second state is where a signal from the modulated laser source is directed to the controller, such as to allow real-time control of the source of the transmitting laser and modulator by the controller.

An optical signal transmitting device comprises an optical transmitter and a mode converter. The optical transmitter transmits a multi-path transmitted initial optical signal to the mode converter, wherein the initial optical signal comprises a first optical signal and a second optical signal both having a first wavelength, and a third optical signal having a second wavelength different from first wavelength. The mode converter is configured to perform phase conversion on the incident initial optical signal to obtain and reflect a first target optical signal, which is single-path transmitted and comprises the third optical signal, the first optical signal transmitted in a first mode, and the second optical signal transmitted in a second mode different from the first mode.

A MIMO system comprises a remote radio unit (RRU) and central unit. The RRU comprises: a binary phase shift keying (BPSK) modulator, configured to modulate a BPSK waveform by a local oscillator (LO) signal to generate a stimulus signal, wherein the LO signal is derived from a downlink optical signal received via downlink radio over fiber (DL-ROF) from a central unit (CU); and an optical signal generator, in particular a laser, configured to generate an uplink optical signal based on the stimulus signal for transmission via uplink radio over fiber (UL-ROF) to the CU.

An optical assembly is used for communicating laser light from a plurality of laser sources into channels for an optical network. The optical assembly comprises an optical substrate, an input optic, at least one Z-block, filters, at least one fiber collimator, and at least one delivery fiber. The input optic is disposed on the optical substrate and is configured to receive the laser light from the laser sources. The input optic is configured to collimate the laser light into a plurality of collimated laser beams. The at least one Z-block is disposed on the substrate and has an input surface and an output surface. The input surface has a plurality of filters disposed thereon, and the input surface is disposed at an angle of incidence relative to the collimated beams from the input optic. The output surface is disposed parallel to the input surface and can have at least one isolator. The at least one Z-block is configured to multiplex the collimated laser beams into at least one output signal having a plurality of the channels. At least one fiber collimator disposed on the substrate has an input and an output. The input is disposed in optical communication with the at least one Z-block and is configured to receive the output signal. The at least one delivery fiber is optically coupled to the output of the at least one fiber collimator and is configured to conduct the optical signal to a receptacle.

An optical device includes an optical coupler that inputs an optical signal received from a light source, a semiconductor optical amplifier that amplifies the optical signal received from the optical coupler, and a light receiving element that receives spontaneous emission light received from the semiconductor optical amplifier. The optical coupler includes a first input port to which the optical signal received from the light source is input, a second input port that is connected to an input stage of the light receiving element and that is different from the first input, and an output port that is connected to an input stage of the semiconductor optical amplifier, and that outputs optical signal received from the first input port to the semiconductor optical amplifier. The light receiving element receives, via the output port and the second input port, spontaneous emission light received from the semiconductor optical amplifier.

Embodiments of the present disclosure include optical transmitters and transceivers with improved reliability. In some embodiments, the optical transmitters are used in network devices, such as in conjunction with a network switch. In one embodiment, lasers are operated at low power to improve reliability and power consumption. The output of the laser may be modulated by a non-direct modulator and received by integrated optical components, such as a modulator and/or multiplexer. The output of the optical components may be amplified by a semiconductor optical amplifier (SOA). Various advantageous configurations of lasers, optical components, and SOAs are disclosed. In some embodiments, SOAs are configured as part of a pluggable optical communication module, for example.

Provided are a single-photon source device and a single-photon source system including same. The single-photon source device includes a substrate, a straight waveguide extending in a first direction on the substrate, a first coupling layer which is provided on the straight waveguide and has a first point defect, at least one first electrode which is adjacent to the first point defect and provided on the first coupling layer, a ring waveguide which is adjacent to the straight waveguide and provided on the substrate, and at least one second electrode provided on the ring waveguide.