Systems, methods, and other embodiments for a new compact narrowband diode-pumped solid-state laser device enabled by Volume Bragg Grating (VBG) technology and capable of operating at the watt or higher output power level. This laser is stable, operates in a transverse electromagnetic (TEM) output mode, and with a single-narrowband (<1 kHz FWHM) longitudinal mode with acceptable relative intensity noise (RIN) performance from 1-100 GHz. In a preferred embodiment of the present invention, the TEM output mode is a TEM.sub.00 Gaussian output mode.

An optical apparatus includes one or more pump sources situated to provide laser pump light, and a gain fiber optically coupled to the one or more pump sources, the gain fiber including an actively doped core situated to produce an output beam, an inner cladding and outer cladding surrounding the doped core and situated to propagate pump light, and a polymer cladding surrounding the outer cladding and situated to guide a selected portion of the pump light coupled into the inner and outer claddings of the gain fiber. Methods of pumping a fiber sources include generating pump light from one or more pump sources, coupling the pump light into a glass inner cladding and a glass outer cladding of a gain fiber of the fiber source such that a portion of the pump light is guided by a polymer cladding surrounding the glass outer cladding, and generating a single-mode output beam from the gain fiber.

A broad line red light generator is configured with a single mode (SM) pulsed ytterbium (“Yb”) fiber laser pump source outputting pump light in a fundamental mode (“FM”) at a pump wavelength which is selected from a 1030-1120 nm wavelength range. The disclosed generator further includes a SM fiber Raman converter spliced to an output of the Yb fiber laser pump source. The Raman converter induces an “n” order frequency Stokes shift of the pump light to output the pump light at a Raman-shifted wavelength within 1220 and 1300 nm wavelength range with a broad spectral line of at least 10 nm. The disclosed light generator further has a single pass second harmonic generator (“SHG”) with a lithium triborate (“LBO”) nonlinear optical crystal having a spectral acceptance linewidth which is sufficient to cover the broad spectral line of the pump light. The SHG generates a SM pulsed broad-line red light with a broad spectral line of at least 4 nm.

A single mode fiber pulsed oscillator includes an all normal dispersion ring cavity provided with a mode-locking fiber loop component and a giant chirp generating fiber component. The mode-locking fiber loop component is configured with a hybrid of NOLM and NALM configurations which is operative to induce a first phase acquisition of a spectrally narrow pulse due to SPM. The giant chirp generating fiber loop component is configured to induce the additional phase acquisition to the pulse broadened in the mode-locking fiber component so as to generate a pulse with a giant chirp. The fiber loop components each include a fiber amplifier and a coil of fiber. The amplifiers each are configured with an active fiber provided with a core which supports multiple transverse mode in a range of wavelength except for the desired wavelength at which the core is configured to support a single fundamental mode.

A vertical external cavity surface emitting laser (VECSEL) based system in a linear single cavity configuration is configured to deliver light in higher-order Hermite-Gaussian transverse modes with Watt-level output power. Simultaneous and independent lasing of spatially-restructurable multiple high-order transverse modes that are collinearly-propagating at the output of such laser cavity is facilitated with the use of an optical pumping scheme devised to control positions of location at which the gain medium of the system is pumped (e.g., locations of focal spots of multiple pump beams on the gain-medium chip). An external astigmatic mode converter is utilized to convert such high-order Hermite-Gaussian modes into corresponding Laguerre-Gaussian modes.

Rare earth doped fiber lasers can be robust and efficient sources of high quality light, but are usually limited to the highest gain transitions of the active species. But rare earths typically possess a multitude of potentially useful transitions that might be accessed if the dominant transition can be suppressed. In fiber lasers this suppression is complicated by the very high net gain the dominant transitions exhibit; effective suppression requires some mechanism distributed along the length of the fiber. We have developed a novel waveguide with resonant leakage elements that frustrate guidance at well-defined and selectable wavelengths. Based on this waveguide, we have fabricated a Large Mode Area Neodymium doped fiber with suppression of the four-level transition around 1060 nm, and demonstrated lasing on the three-level transition at 930 nm with good efficiency.

The subject invention includes a semiconductor laser with the laser having a DBR mirror on a substrate, a quantum well on the DBR mirror, and an interior CGH with a back propagated output for emitting a large sized Gaussian and encircling high energy. The DBR mirror has a plurality of GaAs/AlGaAs layers, while the quantum well is composed of AlGaAs/InGaAs. The CGH is composed of AlGaAs.

An Nd.sup.3+ optical fiber laser and amplifier operating in the wavelength range from 1300 to 1450 nm is described. The fiber includes a rare earth doped optical amplifier or laser operating within this wavelength band is based upon an optical fiber that guides light in this wavelength band. The waveguide structure attenuates light in the wavelength range from 850 nm to 950 nm and from 1050 nm to 1150 nm.

An active element added-optical fiber includes a core, having a radius d and including a first region and a second region, and a cladding that surrounds an outer peripheral surface of the core without a gap and propagates light in a few mode. The first region is a region from a central axis of the core to a radius ra and contains ytterbium as an active element. The second region is a region to the radius d that surrounds the first region without a gap and contains a plurality of dopants, one of which is germanium. The active element is not added to a region within the second region from a radius rc to the radius d. The germanium is not added to a region within the first region from the central axis to a radius rb, and a concentration of the germanium is highest among the plurality of dopants.

A laser system for generating optical pulses at an operating wavelength of the laser system. The system has an optical resonator comprising first and second reflectors, and a tapered optical fiber disposed between the first and second reflectors. The tapered optical fiber has a core which has a tapered input section which tapers from single mode to multimode at the laser operating wavelength, an inner section of substantially constant diameter capable of supporting multiple modes at the laser operating wavelength and a tapered output section which tapers from a first diameter to a second diameter that is smaller than the first diameter.