Sub-100  fs Tm:MgWO4 laser at 2017  nm mode locked by a graphene saturable absorber.

We present the first sub-100 fs bulk solid-state laser in the 2-μm spectral range employing the monoclinic Tm3+-dopedMgWO4 crystal as an active medium. By applying a graphene-based saturable absorber and chirped mirrors for dispersion management, stable self-starting mode-locked operation at 2017 nm was achieved. Nearly Fourier-limited pulses as short as 86 fs featuring a bandwidth of 53 nm were generated at a repetition rate of 76 MHz. A pulse energy of 1.1 nJ was achieved at 87 MHz for a pulse duration of 96 fs. The mode-locked Tm3+:MgWO4 laser exhibits excellent stability with a fundamental beat note extinction ratio of 80 dBc above noise level.

[1]  U. Keller,et al.  Self-referencable frequency comb from a 170-fs, 1.5-μm solid-state laser oscillator , 2010 .

[2]  W. Sibbett,et al.  Passively mode locked femtosecond Tm:Sc2O3 laser at 2.1 μm. , 2012, Optics letters.

[3]  U. Griebner,et al.  Crystal growth, optical spectroscopy and laser action of Tm3+-doped monoclinic magnesium tungstate. , 2017, Optics express.

[4]  Cesar Jauregui,et al.  Impact of atmospheric molecular absorption on the temporal and spatial evolution of ultra-short optical pulses. , 2015, Optics express.

[5]  Valentin Petrov,et al.  Frequency down-conversion of solid-state laser sources to the mid-infrared spectral range using non-oxide nonlinear crystals , 2015 .

[6]  Takao Fuji,et al.  Sub-50-fs pulse generation from thulium-doped ZBLAN fiber laser oscillator. , 2014, Optics express.

[7]  G. Huber,et al.  Broadband emission and laser action of Cr 3+ doped zinc tungstate at 1 µm wavelength , 1985 .

[8]  Wilson Sibbett,et al.  Broadly tunable femtosecond Tm:Lu2O3 ceramic laser operating around 2070 nm. , 2012, Optics express.

[9]  Zhenhua Ni,et al.  Atomic‐Layer Graphene as a Saturable Absorber for Ultrafast Pulsed Lasers , 2009, 0910.5820.

[10]  Fabian Rotermund,et al.  High-quality, large-area monolayer graphene for efficient bulk laser mode-locking near 1.25 μm. , 2011, Optics letters.

[11]  Antoine Godard,et al.  Infrared (2–12 μm) solid-state laser sources: a review , 2007 .

[12]  Lizhen Zhang,et al.  Thermal and spectral characterization of Cr3+:MgWO4—a promising tunable laser material , 2016 .

[13]  Lingyun Li,et al.  Characterization of growth, optical properties, and laser performance of monoclinic Yb:MgWO_4 crystal , 2016 .

[14]  Tamer F. Refaat,et al.  Twenty years of Tm:Ho:YLF and LuLiF laser development for global wind and carbon dioxide active remote sensing , 2015 .

[15]  Konstantin L. Vodopyanov,et al.  Optical THz‐wave generation with periodically‐inverted GaAs , 2008 .

[16]  N. Coluccelli,et al.  Single-clad Tm-Ho:fiber amplifier for high-power sub-100-fs pulses around 1.9 μm. , 2013, Optics letters.

[17]  H. Eichler,et al.  High-gain Raman induced multiple Stokes and anti-Stokes generation in monoclinic multiferroic MnWO4 single crystals , 2007 .

[18]  Hermann A. Haus,et al.  Broadly tunable sub‐500 fs pulses from an additive‐pulse mode‐locked thulium‐doped fiber ring laser , 1995 .

[19]  Xavier Mateos,et al.  Femtosecond Pulses near 2 µm from a Tm:KLuW Laser Mode-Locked by a Single-Walled Carbon Nanotube Saturable Absorber , 2012 .

[20]  Liejia Qian,et al.  Wavelength-Versatile Graphene-Gold Film Saturable Absorber Mirror for Ultra-Broadband Mode-Locking of Bulk Lasers , 2014, Scientific Reports.

[21]  Chennupati Jagadish,et al.  Multipulse operation of a Ti:sapphire laser mode locked by an ion-implanted semiconductor saturable-absorber mirror , 1999 .

[22]  U. Griebner,et al.  Monoclinic Tm3+:MgWO4: a promising crystal for continuous-wave and passively Q-switched lasers at ∼2  μm. , 2017, Optics letters.

[23]  Günter Steinmeyer,et al.  Passive mode-locking of a Tm-doped bulk laser near 2 microm using a carbon nanotube saturable absorber. , 2009, Optics express.

[24]  Günter Steinmeyer,et al.  Boosting the Non Linear Optical Response of Carbon Nanotube Saturable Absorbers for Broadband Mode‐Locking of Bulk Lasers , 2010 .

[25]  W Sibbett,et al.  Femtosecond (191 fs) NaY(WO4)2 Tm,Ho-codoped laser at 2060 nm. , 2010, Optics letters.

[26]  Xavier Mateos,et al.  Growth and properties of KLu(WO4)2, and novel ytterbium and thulium lasers based on this monoclinic crystalline host , 2007 .

[27]  Günter Huber,et al.  175 fs Tm:Lu2O3 laser at 2.07 µm mode-locked using single-walled carbon nanotubes. , 2012, Optics express.