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We report a double-pass bismuth-doped fiber amplifier operating in the O-band with a 31dB gain and a 7dB NF for −10dBm input signal. The amplifier power conversion efficiency and gain-coefficient are 11% and 0.06dB/mW, respectively.

Thulium-doped aluminosilicate fiber fabricated by MCVD process combining both solution doping and gas phase. Laser characterization report a slope efficiency of ∼72% with respect to launched pump power at 2069nm emission wavelength.

We report a ps-MOPA using an efficient ytterbium-doped Al-P-SiO 2 fiber fabricated by MCVD solution-doping process, generating 35kW peak-power pulses at 1035nm with repetition-rate 1.47MHz and average power 9.1W. The optical conversion efficiency was 76%.

We report an efficient thulium-doped fiber offering a laser efficiency >70% with respect to the absorbed pump power over a wide wavelength band of 1890 to 2080nm when cladding pumped at 793nm.

We demonstrate an efficient ytterbium-doped alumino-phospho-silicate low-NA fiber fabricated by modified solution-doping process that shows continuous-wave laser efficiency of 81%. In ps-MOPA, the fiber provides 35kW peak power with repetition-rate 1.46MHz, and average power 9.1W.

A spatially gain-tailored fiber Raman laser with Ge-doped core and P-doped inner cladding generates 46 W of instantaneous power at 1084 nm with 64% slope efficiency when cladding-pumped by a 1030-nm quasi-cw multimode disk laser.

We review all-solid trench-assisted fiber designs for mode-area scaling in flexible fibers. Our proposed fiber designs offer great potential for power scaling of monolithic single-mode fiber laser systems and for high-brightness laser beam delivery

An optical flat-fiber substrate is presented for refractive index sensor. A series of Bragg grating is used as a sensing tool. A maximum sensitivity to approximately 95 nm per refractive index unit has been achieved.

We present a suite of silica-based thulium-doped fiber amplifiers (TDFAs) operating across the 1650–2050nm waveband. High gain and low NF are achieved by combining several TDFA designs optimized for short, central and long wavelength operation.

We present a single transceiver based modal characterization method for estimating the channel impulse response of MDM systems. Good agreements are found between the measured and simulated DGDs of a RCF supporting 5 mode groups.

We demonstrate mode-group division multiplexing over 100m graded-index ring-core fiber supporting 4 LP mode-groups with a single radial index using SLM-based mode (de)multiplexers to transmit 2×10Gbps NRZ signals without MIMO equalization.

We design and characterize a graded-index-ring-core fiber supporting 7 LP mode-groups (13 spatial modes) for mode multiplexed transmission with low MIMO processing complexity. Spatial and temporal modal properties are analyzed using an SLM-based mode multiplexer/demultiplexer.

We report the realization of a wideband holmium doped fiber amplifier designed for optical communications over 2050 – 2130 nm, providing up to 28 dB small signal gain and 4 – 9.5 dB noise figure.

We demonstrate an ultra-low-NA (~0.038) Yb-doped step-index-fiber fabricated using conventional MCVD and solution-doping process. The fiber ensures ~700µm2 Aeff for effective-single-mode operation and 81% laser efficiency with M2 ~1.1 at a bend diameter of 32cm.

We review the progress towards multi-trench fibers for high power fiber laser applications. Such fiber designs address several challenges associated with power scaling of high power fiber laser.

A cladding-pumped multi-element fiber comprising 4-Er/Yb-doped signal fibers and single multimode pump fiber has been used to demonstrate a C+L split-band amplifier. The signal fibers were cascaded to provide >20dB gain over 80nm bandwidth.

We propose a novel fiber that offers excellent suppression of higher-order-modes with loss higher than 10dB/m and low loss for fundamental mode (

We report the fabrication and characterisation of rare-earth-doped multicore optical fiber with the aim to develop multi-band optical fiber laser sources and amplifiers to exploit future novel multicore fiber laser and amplifiers.

We present a 2-mode group, switchable spatial mode erbium doped fiber laser incorporating a spatial light modulator. The laser wavelength can be tuned using an intra-cavity wavelength selective filter and provides >10dB extinction ratio between LP01/LP11 modes.

The recently observed self-phasing of coherently coupled fibers due to Kramers-Kronig effects is theoretically described using a simple model. Direct measurements of the Kramers-Kronig effect and Henry’s alpha parameter are reported.

We present the first demonstration of nanosecond-pulsed fiber MOPA systems seeded by semiconductor laser diodes at 2 μm incorporating arbitrary pulse shaping capabilities, achieving up to 1.0 mJ (12.5 kHz, 100 ns) pulse energy.

A cladding-pumped dual core ytterbium fiber laser is designed and fabricated to measure phase error tolerance in passive coherent beam combining. We show quantitative measurements on the effects of longitudinal modes on phase error tolerance.

We demonstrate an efficient cladding-pumped multi-element fiber comprising 4-Er/Yb-doped signal and 1-multimode pump fibers drawn together in a common coating. The signal fibers were cascaded to achieve a flat-gain (36±1dB) in the wavelength range 1544-1565nm.

Thermal effects are becoming increasingly problematic in fiber lasers as the powers get higher, the cores larger, and the fibers shorter. We discuss high-brightness tandem-pumping, and how it can drastically reduce the thermal load. Article not available.

We present a multi-trench-fiber, in which high-index-rods are included along one of its axis. Numerical simulation shows excellent filtering of higher-order-modes (>10dB/m) at 1060nm and Stimulated-Raman-Scattering (>60dB/m) at 1116nm for Aeff (>520µm2) with good bend-robustness.

The spontaneous Brillouin spectrum of an aluminosilicate fiber shows two distinct peaks. Respective linewidths exhibit strain coefficients of 0.0204±0.0043MHz/µ.epsilon and 0.02374±0.0053MHz/µ.epsilon and temperature coefficients of -0.66±0.2447MHz/°C and 0.50±0.1459MHz/°C

We report on the spectroscopy and laser characteristics of Nd-doped fiber, fabricated by rod-in-tube from Nd:YAG as a core material with silica cladding. A cladding-pumped CW laser operation at 1058nm with 52% slope-efficiency is demonstrated.

The spontaneous Brillouin spectrum of an aluminosilicate fiber shows two distinct peaks. Strain and temperature coefficients of 0.0392±0.0027MHz/µ.epsilon, 1.5±0.2MHz/°C for Peak 1 and 0.031±0.0025MHz/µ.epsilon, 1.1±0.1MHz/°C for Peak 2 is obtained for exploitation in temperature-strain distinction

We show transmission of a 73.7 Tb/s (96x3x256-Gb/s) DP-16QAM modedivision- multiplexed signal over 119km of few-mode fiber with inline multi-mode EDFA, using 6x6 MIMO digital signal processing. The total demonstrated net capacity is 57.6 Tb/s (SE 12 bits/s/Hz) Refereed/Peer-reviewed

We report a crosstalk-free Er-doped amplifier consisting of 3-fibers, each behaving as a single fiber in isolation. 32dB of gain and

Experiments on core- and cladding-pumped Er-doped fiber lasers demonstrate that the output power more than double when they are cooled from room temperature to liquid-nitrogen temperature, reaching 95 mW and 1.21 W for core and cladding-pumping fiber lasers respectively in the “eye-safe” emission band around 1.6 μm. The results are explained in terms of the spectroscopy of Er at lower temperature, which gets closer to the outstanding spectroscopy of Yb:silica.

We report on the fabrication and characterization of an YDFL with a pedestal geometry fabricated using an in-situ solution doping process. The fiber has a unique non-stressed inner-cladding and exhibits good efficiency.

A novel method for selectively exciting a single-spatial-mode (fundamental or higher-order) in a high-power multi-mode fiber laser resonator is presented. Preliminary results for a cladding-pumped Tm-doped silica fiber laser are discussed.

We describe a simple approach for efficient generation of visible light in high-power continuous-wave fiber lasers via second harmonic generation in an internal resonant cavity. Preliminary results for a cladding-pumped Yb fiber laser are presented.

We report a highly versatile gas phase technique for making ytterbium doped silica fibers. Initial results generated 200W output power with a slope efficiency of 72%.

Thulium-doped silica fiber lasers and amplifiers offer a route to very high average power in the two-micron wavelength regime. This presentation reviews recent progress and considers the prospects for further improvement in performance.

We investigated the performance of Bi-doped fiber amplifier at 1179 nm, in both low and high input signal regime, when pumped at 1090 nm. The amplifier efficiency and the saturation power both depend on the fiber cooling.

An in-band pumped thulium-doped distributed-feedback fiber laser is reported. The laser produced 318 mW of output power at 1935 nm with a slope efficiency of 21% with respect to absorbed pump power.

We report 5-ps pulses at 160 W average power and 910 MHz repetition rate from a passively mode-locked VECSEL source seeding an Yb-doped fibre power amplifier. The amplified pulses were compressed to 291 fs duration.

Electro-optically Q-switched operation of an Er:YAG laser at 1645 nm end-pumped by a cladding-pumped Er,Yb fiber laser is reported. Pulse energies up to 15 mJ have been generated at a pulse repetition frequency of 29Hz.

Highly efficient room-temperature operation of an Er:YAG laser end-pumped by a high-power cladding-pumped tunable Er,Yb fiber laser operating at 1532 nm is reported. Using a simple four-mirror folded-resonator configuration, we obtained > 60W of continuous-wave output at 1645nm for 82W of incident pump power. The corresponding slope efficiency was 80.7%.

A high-power and ultra-efficient cladding-pumped Tm-doped silica fiber laser is reported. The laser produced 30.8W of output at 2025nm for 58.5W of launched pump power, and the corresponding slope efficiency was 61%.

Efficient single-mode operation of a cladding-pumped ytterbium-doped multimode helical-core fiber laser has been demonstrated. The laser yielded 60.4W of output at 1043nm in a beam with M2

We review recent advances of high-power fiber lasers and amplifiers based on the latest experimental results. Key technologies that led to kilowatt level fiber based devices and the potential for further progress will be discussed.

We demonstrate an in-band pumped (1565 nm) continuous-wave (CW) single-frequency distributed-feedback fibre laser operating at 1836 nm with an output power of ~5 mW and amplified to 345 mW using a master-oscillator power amplifier configuration.

We propose and demonstrate a depressed-clad hollow fiber structure for an efficient cladding-pumped 930nm Nd-doped fiber laser. It generated 3.3W of single-mode continuous-wave output, and 133 micro-J of pulse energy at 5kHz repetition-rates when Q-switched.

We describe a cladding-pumped erbium-ytterbium co-doped fiber laser with 120 W of output at 1.57μm and with a slope efficiency of 40% with respect to launched pump power. No roll-off in output power was observed

A cladding pumped neodymium-doped fiber laser tunable from 932 nm to 953 nm produced a single-mode laser output with maximum power 705 mW at 944 nm. An effective design was used to avoid competing four level transition.

A cladding pumped neodymium-doped fiber laser tunable from 932 nm to 953 nm produced a single-mode laser output. A maximum power of 705 mW was measured at 944 nm. A W-profile core refractive index suppressed competing four-level emission at 1090 nm. The results are compared with numerical simulations based on measured physical parameters.