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.

Apparatus and methods for producing ultrashort optical pulses are described. A high-power, solid-state, passively mode-locked laser can be manufactured in a compact module that can be incorporated into a portable instrument for biological or chemical analyses. The pulsed laser may produce sub-100-ps optical pulses at a repetition rate commensurate with electronic data-acquisition rates. The optical pulses may excite samples in reaction chambers of the instrument, and be used to generate a reference clock for operating signal-acquisition and signal-processing electronics of the instrument.

A fiber laser system based in solitonic passive mode-locking, including a laser diode to emit and deliver an optical signal of a first wavelength; a single-fiber laser cavity including a dichroic mirror, a SESAM and a polarization maintaining highly-doped active fiber, to receive the emitted signal and to emit a pulsed optical signal of a second wavelength, generating laser light in the form of mode-locked ultrashort pulses; a unit coupling the laser diode to the single-fiber laser cavity; and an isolator device protecting the cavity from back reflections. The solitonic mode-locked ultrashort pulses are comprised in a range of 100 fs<10 ps with repetition rates of hundreds MHz to tens of GHz.

A mode locking device is disclosed for altering repetition rate in a mode-locked laser. In an example device, laser light is coupled from a fiber into a cavity through a sliding pigtail collimator with a diameter selected such that it is a close tolerance fit with a female snout on a package. A lens focuses laser light to an appropriate spot size onto a SAM or SESAM, such that back-reflection into the fiber is maximized. A piezoelectric transducer is mounted in cooperation with the SAM or SESAM for cavity tuning.

An all-fiber airtight packaging structure with semiconductor saturable absorber mirror includes a ceramic optical fiber ferrule connector, a SESAM, a SESAM fixed block, a TEC chilling plate, a sealing shell, and a cover plate. The cover plate seals the sealing shell by connecting to a sealing shell surface. The TEC chilling plate and the SESAM fixed block are set in the sealing shell. The SESAM fixed block is located above the TEC chilling plate. The SESAM is pasted on the SESAM fixed block. A sealing shell central hole is defined in the sealing shell. The ceramic optical fiber ferrule connector is entered into the sealing shell through the sealing shell central hole, and an output end of ceramic optical fiber ferrule connector is opposited to an end of SESAM which is mounted on the SESAM fixed block.

A quasi-monolithic solid-state laser in which the optical components of the laser cavity are bonded to a common substrate via mounts. The optical components and their mounts are fixedly connected to each other and to the substrate by bonding. While the gain medium is bonded to a mount made of a different material with high thermal conductivity for heat sinking, the cavity's lens and mirror components and their mounts are all made of the same material as the substrate, or a different material that is thermally matched to the substrate, and fixedly mounted on the substrate solely with bonding. The bonding is achieved with adhesive bonding, or some other form of bonding such as molecular bonding, chemically activated direct bonding or hydroxide catalysis bonding.

A radiation field generating system comprising an optical unit with an optical assembly which defines an optical path is provided, wherein the optical unit is operable in several different operation conditions and the optical assembly comprises at least one optical switching component with which switching between at least two different operation conditions of the several operation conditions can be performed.

A fiber laser system based in solitonic passive mode-locking, including a laser diode to emit and deliver an optical signal of a first wavelength; a single-fiber laser cavity including a dichroic mirror, a SESAM and a polarization maintaining highly-doped active fiber, to receive the emitted signal and to emit a pulsed optical signal of a second wavelength, generating laser light in the form of mode-locked ultrashort pulses; a unit coupling the laser diode to the single-fiber laser cavity; and an isolator device protecting the cavity from back reflections. The solitonic mode-locked ultrashort pulses are comprised in a range of 100 fs<10 ps with repetition rates of hundreds MHz to tens of GHz.

Disclosed herein is an all-fiber, easy to use, wavelength tunable, ultrafast laser based on soliton self-frequency-shifting in an Er-doped polarization-maintaining very large mode area (PM VLMA) fiber. The ultrafast laser system may include an all polarization-maintaining (PM) fiber mode-locked seed laser with a pre-amplifier; a Raman laser including a cascaded Raman resonator and an ytterbium (Yb) fiber laser cavity; an amplifier core-pumped by the Raman laser, the amplifier including an erbium (Er) doped polarization maintaining very large mode area (PM Er VLMA) optical fiber and a passive PM VLMA fiber following the PM Er VLMA, the passive PM VLMA for supporting a spectral shift to a longer wavelength.

An optical assembly provides dispersion control, modelocking, spectral filtering, and/or the like in a laser cavity. For example, the optical assembly may comprise a diffraction grating pair arranged to temporally and spatially disperse a beam on a forward pass through the optical assembly, a reflective device at an end of the optical assembly, and a focusing optic arranged to create a beam waist at the reflective device. The beam waist created at the reflective device may cause the beam to be inverted on a reverse pass through the optical assembly, and a temporal dispersion and a spatial dispersion of the beam may be doubled on the reverse pass through the optical assembly to form a temporally and spatially dispersed output from the optical assembly.