The invention relates to a multi-wavelength synchronous output fiber laser based on nonlinear polarization rotation mode locking, which comprises a semiconductor laser, a wavelength division multiplexer, a gain fiber, a first collimating mirror, a first half wave plate, a first quarter wave plate, a first polarization beam splitter, a Faraday isolator, a glaring grating, and a silver mirror According to the first half wave plate, a nonlinear polarization rotation technology is adopted for mode locking, a saturable absorber which is likely to be damaged can be prevented from being used, and the stability of the laser is enhanced According to the same laser gain fiber and the nonlinear polarization mode locking device, the distance between two wavelengths under mutual cross phase modulation effects in the laser cavity is increased, and thus, a cavity length misadjustment range for two laser cavities in the case of synchronous mode locking can be increased Through changing the angle of a beam-splitting grating, the output wavelength of the laser can be tuned, the gap between the two wavelengths can be changed through changing the position of the collimator in the spectral space, and through changing the position of the collimator away from the beam-splitting grating, the pulse spectral width and the pulse width of laser output pulses can be changed

Multi-wavelength synchronous output fiber laser based on nonlinear polarization rotation mode locking

The invention relates to an optical frequency comb device based on an all polarization-maintaining fiber and a mode locking and frequency locking method. The generation of mode locking pulses is realized by nonlinear polarization rotation of the pulses in a spiral fiber. The repetition rate of the device is locked through a mechanical method or an optical method. Through an all polarization-maintaining fiber amplifier, a polarization-maintaining nonlinear fiber and a PPLN crystal, carrier phase zero frequency signals of the pulses are acquired; the carrier phase zero frequency signals are processed by a circuit and are then fed back to a power control device in the device or fed back to an intracavity loss control device, and locking of the carrier phase zero frequency signals is realized.Based on the all polarization-maintaining fiber, a mode-locked laser is built, the pulses generate nonlinear polarization rotation in the spiral fiber, and walk-off effects of the pulses are solved through special arrangement of multiple sections of spiral fibers. The made all polarization-maintaining fiber optical frequency comb device has the characteristics of extremely high stability and insensitivity to temperature fluctuation and mechanical vibration.

Optical frequency comb device based on all polarization-maintaining fiber and mode locking and frequency locking method

The invention discloses a system and a method for generating a small-mode laser beam on a chip based on silicon-based mode conversion The invention belongs to the field of integrated optics The system comprises a silicon-based waveguide (1) and an optical fiber system (2), wherein, the silicon-based waveguide (1) comprises a silicon-based waveguide coupler (14, 15), a few-mode silicon-based modemultiplexer (16)/demultiplexer (13), a few-mode silicon-based waveguide (12), and a few-mode silicon-based power coupler (14); The optical fiber system (2) includes a pump source (24), an optical isolator (23), an erbium-doped optical fiber (26), a single-mode optical fiber (22), an optical wavelength division multiplexer (25), an optical channel selector (27), and an optical coupler (21) The system uses semiconductor laser as pump source, erbium-doped fiber as gain medium, fiber system and silicon-based waveguide to construct ring resonator, and generates few-mode laser by controlling silicon-based mode conversion, which provides an effective technical scheme for the construction of high-density system on chip

System and method for generating small-mode laser beam on chip based on a silicon-based mode conversion

The invention discloses a picosecond fiber seed laser which comprises a fiber oscillator, a fiber pre-amplifier and a fiber main amplifier; the fiber oscillator comprises a semiconductor saturable absorption lens, a first gain fiber, a grating, a first semiconductor pumping source, a first wavelength division multiplexer and a first fiber isolator; the fiber pre-amplifier comprises a second wavelength division multiplexer, a second pumping source, a second gain fiber, an acousto-optic modulator and a second fiber isolator; and the fiber main amplifier comprises a third wavelength division multiplexer, a third semiconductor pumping source and a third gain fiber. The picosecond fiber seed laser is higher in monopulse energy and output power, and lowers requirement for the gain capability ofa subsequent amplifier.

Picosecond fiber seed laser

A passive mode-locking fiber laser based on nonlinear polarization rotation and a compound cavity structure is composed of a traditional nonlinear polarization rotation laser and a frequency selective device, a polarization controller 2 is connected with the common terminal d of a polarization beam splitter 2, the output ends e and f of the polarization beam splitter 2 are connected with single-mode fibers 6 and 7 at the two ends respectively, the other ends of the single-mode fibers at the two ends are connected with a polarization controller 3 and a polarization controller 4 respectively, the other ends of the polarization controller 3 and the polarization controller 4 are connected with the input ends g and h of a polarization beam combiner, and the common terminal i of the polarization beam combiner is connected with the input end of an erbium-doped fiber amplifier. The formed closed loops become resonant cavities of the passive mode-locking laser, and the two compound cavities jointly select frequency, so that the fundamental frequency of the cavities of the laser is increased, and the repetition frequency of pulses becomes higher. The laser has the advantages of being simple in structure, low in cost, high in pulse repetition frequency, large in pulse width, and capable of stably working at normal temperature.

Passive mode-locking fiber laser based on nonlinear polarization rotation and compound cavity structure

The invention discloses a figure-of-eight cavity and composite cavity structure-based passive mode-locked fiber laser, which is characterized in that a frequency-selecting structure is added into the traditional figure-of-eight cavity structure laser; in the figure, one port of a polarization controller 2 is connected with the common port k of a polarization beam splitter; another two ports of the polarization beam splitter are respectively connected with two polarization controllers 3 and 4; the other end of the polarization controller 3 and the other end of the polarization controller 4 are respectively connected with two sections of single mode fibers 1 and 2; the other end of the single mode fiber 1 and the other end of the single mode fiber 2 are respectively connected with the n port and the o port of a polarization beam combiner; the common port p of the polarization beam combiner is connected with the common port b of a wavelength division multiplexer; a formed closed loop circuit becomes a resonant cavity of the passive mode-locked fiber laser, and composite double cavities are jointly used for frequency selecting, so that the fundamental frequency of each cavity of the laser becomes large, and the pulse repetition rate becomes high. The passive mode-locked fiber laser disclosed by the invention has the advantages of being simple in structure, low cost, high in pulse repetition rate, narrow in pulse width, and the like, and can stably work at normal temperature.

Figure-of-eight cavity and composite cavity structure-based passive mode-locked fiber laser

The invention discloses a figure-of-eight cavity and silicon-based microannulus structure-based passive mode-locked fiber laser, which is characterized in that a frequency-selecting device is added on the basis of the traditional figure-of-eight cavity structure; one port of a polarization controller 2 is connected with a silicon-based microannulus; a formed closed loop circuit formed by connecting the other end of the silicon-based microannulus with the b port of a wavelength division multiplexer becomes a resonant cavity of the passive mode-locked fiber laser, and composite double cavities are jointly used for frequency selecting, so that the fundamental frequency of each cavity of the laser becomes large, and the pulse repetition rate becomes high. The passive mode-locked fiber laser disclosed by the invention has the advantages of being simple in structure, low cost, high in pulse repetition rate, narrow in pulse width, and the like, and can stably work at normal temperature.

Shi Yanmei

Papers

Passive mode-locking fiber laser based on nonlinear polarization rotation and compound cavity structure

Figure-of-eight cavity and composite cavity structure-based passive mode-locked fiber laser

Figure-of-eight cavity and silicon-based microannulus structure-based passive mode-locked fiber laser