Optical pulse sources. In one example, the pulse source includes an optical fiber ring resonator with at least one normal dispersion fiber segment characterized by a positive group velocity dispersion (GVD) per unit length and at least one anomalous dispersion fiber segment characterized by a negative GVD per unit length. In another example, the pulse source includes an optical fiber ring resonator with one or more fiber segments having a positive net group velocity dispersion (GVD); and an intracavity spectral filter optically coupled to the one or more fiber segments. The pulse source is configured to generate one or more optical solitons in the optical fiber ring resonator.

An integrated Fourier domain mode-locked optoelectronic oscillator and its application and a communication system are provided, which relates to the technical field of microwave photonics. The integrated Fourier domain mode-locked optoelectronic oscillator includes an optoelectronic chip and an electronic chip. The optoelectronic chip includes a laser, a modulator, an optical notch filter, and a photodetector coupled via an optical waveguide. The electronic chip includes an electrical amplifier and a power splitter coupled via a coplanar microwave waveguide. The volume, weight and power consumption of the Fourier domain mode-locked optoelectronic oscillator is greatly reduced by integrating all the devices on the chip. A tunable sweeping microwave signal output is realized, and the sweeping speed of the output signal is increased. The integrated Fourier domain mode-locked optoelectronic oscillator can be used in radars and communication systems.

A wavelength-tunable, polarization-maintaining (PM) fiber laser for use in the two micron wavelength region is based upon a ring laser geometry and includes sections of polarization-maintaining (PM) optical fiber for supporting propagation of the circulating laser radiation around the ring. At least one gain module is included in the ring and is formed of polarization-maintaining active optical fiber including a core region that is doped with either Thulium (Tm) or Holmium (Ho), or co-doped with both of these rare earth materials. In the presence of a pump beam operating at a suitable wavelength, the gain module(s) generate laser radiation at a wavelength within the two micron region. A PM-based tunable bandpass filter (BPF) is included within the ring and used to control/adjust the wavelength of the output beam provided by the fiber laser.

A fiber laser device includes a first optical fiber, a second optical fiber, and a third optical fiber configured by polarization maintaining fibers. The first optical fiber includes at least one first part and at least two second parts alternatively disposed with the first part. The first part and the second part adjacent to each other are connected to each other such that a fast axis of the first part coincides with a slow axis of the second part at a connection point. A total length of the first part is equal to a total length of the second parts. A mode field diameter of the first optical fiber is smaller than each of a mode field diameter of the second optical fiber and a mode field diameter of the third optical fiber.

A method and a system for controlling an output of an optical system, the method comprising generating a plurality of optical signal components having different optical properties and passing the generated optical signal components as input to an optical system comprising an optical device and/or an optical medium; an output of the optical system being based on interactions of the signal components within the optical device and/or the optical medium; and relative proportions of the optical signal components that are generated and individual optical properties thereof being selected to control the output of the optical system.

A laser light source includes an inner ring and an outer ring. The inner ring includes a semiconductor optical amplifier (SOA), a pair of optical circulators, a first optical filter, and a first optical waveguide connecting those in series. The outer ring includes the SOA, a pair of optical circulators, a second optical filter, an output port, and a second optical waveguide connecting those in series except for a portion shared. The inner ring operates as a gain-clamped SOA with a feedback control light defined by the first optical filter. The outer ring generates a laser output in a gain region of the clamped SOA, and with multiple peak wavelengths defined by the second optical filter, in a range from L Band to U band, applicable to WDM network systems. A WDM network system and a method of controlling the laser light source are also disclosed.

A fiber structure includes first and second optical fibers disposed such that end portions thereof butt, a sheet-shaped saturable absorber including a carbon nanotube and disposed between the end portion of the first optical fiber and the end portion of the second optical fiber, and a housing internally accommodating the end portion of the first optical fiber and the end portion of the second optical fiber. A space in the housing including the saturable absorber is airtight.

A single-laser light source system for cold atom interferometers, comprising: a reference light module including a narrow-bandwidth laser and a frequency stabilization module and an optical frequency shift module including a first electro-optic modulator and a first narrow-bandwidth optical-fiber filter. The first electro-optic modulator is connected to the first narrow-bandwidth optical-fiber filter by an optical fiber, and the first electro-optic modulator is connected to the laser by an optical fiber. The first electro-optic modulator receives an initial light from the laser, modulates the initial light by a modulation signal with a preset frequency, and generates sidebands with the preset frequency. The first narrow-bandwidth optical-fiber filter filters the optical signal at the output of the first electro-optic modulator to obtain a frequency-shifted light as the +1-order sideband. The frequency-shifted light is used for modulation to obtain a measurement and control light of the cold atom interferometer.

A pulse stretching fiber oscillator (or laser cavity) may comprise a chirped fiber Bragg grating (CFBG) and an optical circulator arranged such that a first portion of a beam that is transmitted through the CFBG continues to propagate through the laser cavity while a second portion of the beam that is reflected from the CFBG is stretched and chirped by the CFBG and directed out of the laser cavity by the optical circulator. Accordingly, a configuration of the CFBG and the optical circulator in the laser cavity may enable pulse stretching contemporaneous with outcoupling, which may prevent deleterious nonlinear phase from accumulating prior to stretching.

Embodiments relate to a resonator including a graphene layer formed on a support, and a tapered fiber disposed around at least part of the support, close to the graphene layer, wherein the tapered fiber has different paths along which light travels in a region extending from one end and a region extending from the other end, and a passive-mode-locked pulse laser oscillation system including the same.