Kerr-lens mode-locked 49-fs Tm:YScO single-crystal laser at 2.1 µm.

We report on a continuous wave (CW) and Kerr-lens mode-locked (KLM) Tm:YScO single-crystal laser centered at 2.1 µm. Efficient CW laser operation with a maximum slope efficiency of 51% was achieved under in-band pumping by an Er:Yb fiber master oscillator power amplifier (MOPA).

Spectroscopy and 2.1 µm laser operation of Czochralski-grown Tm:YScO crystals.

We report on growth, temperature-dependent spectroscopy, and laser experiments of Tm-doped YScO mixed sesquioxide crystals. For the first time, cm-scale laser quality Tm:YScO crystals with 2.2 at.

Sub-6 optical-cycle Kerr-lens mode-locked Tm:LuO and Tm:ScO combined gain media laser at 2.1 μm.

We present a combined gain media Kerr-lens mode-locked laser based on a Tm:LuO ceramic and a Tm:ScO single crystal. Pulses as short as 41 fs, corresponding to less than 6 optical cycles, were obtained with an average output power of 42 mW at a wavelength of 2.1 μm and a repetition rate of 93.

Nanosecond passively Q-switched fibre laser using a NiS based saturable absorber.

Q-switched pulse laser generation is successfully demonstrated in both Erbium-doped fibre laser (EDFL) and Thulium-doped fibre laser (TDFL) cavities by employing Nickel disulfide (NiS) as a saturable absorber (SA). Q-switched pulse laser operation at 1.55 μm and 2.

All-normal-dispersion nonlinear polarization rotation mode-locked Tm:ZBLAN fiber laser.

We demonstrated an all-normal-dispersion nonlinear polarization rotation mode-locked Tm:ZBLAN fiber laser in the 2 μm wavelength band. All fibers in the experiment were ZBLAN fibers with normal dispersion in the wavelength band. An average power of 63 mW with a characteristic cat-ear shaped optical spectrum of an ANDi laser was obtained.

Kerr-lens mode-locked Tm:ScO single-crystal laser in-band pumped by an Er:Yb fiber MOPA at 1611 nm.

We demonstrate a Kerr-lens mode-locked Tm:ScO single-crystal laser in-band pumped by an Er:Yb fiber master oscillator power amplifier at 1611 nm. Pulses as short as 166 fs with an average output power of 440 mW are obtained. The spectral bandwidth and center wavelength are 29.

Tunable noise-like pulse generation in mode-locked Tm fiber laser with a SESAM.

We report on a tunable noise-like pulse (NLP) generation in a mode-locked Tm fiber laser with a SESAM. A tuning range of 1895-1942 nm, while keeping the spectral bandwidth of 10-19 nm under NLP mode-locked operation, was obtained by a tunable filter based on chromatic dispersion of telescope lenses. At the center wavelength of 1928 nm, the maximum output power of 195 mW with the spectral bandwidth of 18.

High power narrow-linewidth linearly-polarized 1610 nm Er:Yb all-fiber MOPA.

We developed a narrow-linewidth linearly-polarized all-PM-fiber MOPA at the wavelength of 1610 nm. The MOPA consists of a DFB laser diode seed source and three amplifier stages with three different gain fibers. The first amplifier stage employed an Er doped fiber and the second and third amplifier stages employed Er:Yb co-doped fibers.

Exploiting the short wavelength gain of silica-based thulium-doped fiber amplifiers.

Short wavelength operation (1650-1800 nm) of silica-based thulium-doped fiber amplifiers (TDFAs) is investigated. We report the first demonstration of in-band diode-pumped silica-based TDFAs working in the 1700-1800 nm waveband. Up to 29 dB of small-signal gain is achieved in this spectral region, with an operation wavelength accessible by diode pumping as short as 1710 nm.

Numerical analysis of fast saturable absorber mode-locked Yb(3+) lasers under large modulation depth.

Numerical analysis of fast saturable absorber mode-locked Yb(3+)-doped solid state lasers is reported. The analysis includes a special case in which the spectral bandwidth of the short pulse is larger than the fluorescence bandwidth of the gain material. The relationship between the available shortest pulse duration and modulation depth for a standard bulk and thin disk laser geometries with several gain materials are shown.

High resolution Fourier domain optical coherence tomography in the 2 μm wavelength range using a broadband supercontinuum source: erratum.

We correct a mistake in the OCT system sensitivity given in our recent paper [Opt. Express23(3), 1992 (2015)].

Ultra-short wavelength operation of a thulium fibre laser in the 1660-1750 nm wavelength band.

Ultra-short wavelength operation of a thulium fibre laser is investigated. Through use of core pumping and high feedback efficiency wavelength selection, a continuously-tunable fibre laser source operating from 1660 nm to 1720 nm is demonstrated in a silica host. We discuss the range of applications within this important wavelength band such as polymer materials processing and medical applications targeting characteristic C-H bond resonance peaks.

High resolution Fourier domain optical coherence tomography in the 2 μm wavelength range using a broadband supercontinuum source.

A 220 nm bandwidth supercontinuum source in the two-micron wavelength range has been developed for use in a Fourier domain optical coherence tomography (FDOCT) system. This long wavelength source serves to enhance probing depth in highly scattering material with low water content. We present results confirming improved penetration depth in high opacity paint samples while achieving the high axial resolution needed to resolve individual paint layers.

Ultra-broadband wavelength-swept Tm-doped fiber laser using wavelength-combined gain stages.

A wavelength-swept thulium-doped fiber laser system employing two parallel cavities with two different fiber gain stages is reported. The fiber gain stages were tailored to provide emission in complementary bands with external wavelength-dependent feedback cavities sharing a common rotating polygon mirror for wavelength scanning. The wavelength-swept laser outputs from the fiber gain elements were spectrally combined by means of a dichroic mirror and yielded over 500 mW of output with a scanning range from ~1740 nm to ~2070 nm for a scanning frequency of ~340 Hz.

Optical coherence tomography in the 2-μm wavelength regime for paint and other high opacity materials.

An optical coherence tomography system using a compact fiber source emitting amplified spontaneous emission at central wavelength of 1960 nm with bandwidth of 40 nm is developed to enhance the probing depth in a highly scattering material with low water content. Examples of application to paint are used to demonstrate significantly improved penetration depth in high opacity materials in the 2-μm wavelength regime.

Wavelength-swept Tm-doped fiber laser operating in the two-micron wavelength band.

A wavelength-swept thulium-doped silica fiber laser using an intracavity rotating slotted-disk wavelength scanning filter in combination with an intracavity solid etalon for passive control of temporal and spectral profiles is reported. The laser yielded a wavelength swept output in a step-wise fashion with each laser pulse separated from the previous pulse by a frequency interval equal to the free-spectral-range of the etalon and with an instantaneous linewidth of <0.05 nm.

Continuous wave and mode-locked Yb3+:Y2O3 ceramic thin disk laser.

CW and mode-locked laser operation based on an Yb3+:Y2O3 ceramic thin disk is reported. In CW laser operation, an output power of 70 W with an optical-to-optical efficiency of 57.4% was achieved.

Ultrashort pulse generation from diode pumped mode-locked Yb3+:sesquioxide single crystal lasers.

We present diode pumped SESAM supported Kerr-lens mode locked laser operation based on Yb3+:Sc2O3 and Yb3+:Lu2O3 single crystals. Pulses as short as 71 fs with an average power of 1.09 W were obtained from an Yb3+:Lu2O3 single crystal.

Continuous-wave and mode-locked lasers on the base of partially disordered crystalline Yb3+:{YGd2}[Sc2](Al2Ga)O12 ceramics.

We present cw and mode-locked laser operations on the base of partially disordered crystalline Yb(3+):{YGd(2)}[Sc(2)](Al(2)Ga)O(12) ceramics. In continuous-wave laser operations, the average power of 2.9 W at the wavelength of 1051 nm and 2.

Diode-pumped ultrashort-pulse generation based on Yb(3+):Sc(2)O(3) and Yb(3+):Y(2)O(3) ceramic multi-gain-media oscillator.

Diode-pumped mode-locked laser operation based on Yb(3+):Sc(2)O(3) and Yb(3+):Y(2)O(3) multi-gain-media oscillator has been demonstrated. 66-fs pulse duration with an average power of 1.5 W and 53-fs pulse duration with an average power of 1 W under 8-W laser diode pumping were achieved.

Diode-pumped 65 fs Kerr-lens mode-locked Yb(3+):Lu(2)O(3) and nondoped Y(2)O(3) combined ceramic laser.

Diode-pumped Kerr-lens mode-locked laser operation of Yb(3+):Lu(2)O(3) and nondoped Y(2)O(3) combined ceramics has been achieved; 65 fs pulses with an average power of 320 mW under 5 W of pump power were obtained at the center wavelength of 1032 nm. The spectral bandwidth and the time bandwidth product were 18.9 and 0.

Diode-pumped sub-100 fs Kerr-lens mode-locked Yb3+:Sc2O3 ceramic laser.

Diode-pumped Kerr-lens mode-locked laser operations of Yb3+:Sc2O3 ceramics have been achieved. 92 fs pulses with the average power of 850 mW under 3.89 W incident pump power were obtained at a center wavelength of 1042 nm.

Diode-pumped mode-locked Yb(3+):Lu(2)O(3) ceramic laser.

We report a diode-pumped passively mode-locked Yb(3+):Lu(2)O(3) ceramic laser by use of a semiconductor saturable absorber mirror. Almost transform-limited 357 fs pulses at the center wavelength of 1033.5 nm with a maximum average power of 352 mW are obtained.