[Show abstract][Hide abstract] ABSTRACT: We experimentally demonstrate the dissipative soliton mode-locking operation of a Yb:YSO laser by using an all-normal dispersion cavity. Strongly chirped pulses are obtained with pulse duration of 9.3 ps at a repetition rate of 113.4 MHz. The central wavelength is 1082 nm with 3.1 nm FWHM bandwidth. A dual-wavelength synchronously mode-locking operation at central wavelengths of 1059.2 nm and 1082.2 nm is also reported. Stable mode-locked pulses are achieved with pulse duration of 10 ps and total average output power of 164 mW. Periodic ultrashort beat pulses with pulse duration of 169 fs at an ultrahigh repetition rate of 1.4 THz can be distinctly observed from the measured autocorrelation trace. To our knowledge, this is the first demonstration of dual-wavelength synchronously mode-locking operation from a Yb:YSO laser.
[Show abstract][Hide abstract] ABSTRACT: A passively mode-locked femtosecond laser based on an Nd, Y-codoped CaF2 disordered crystal was demonstrated. The Y3+-codoping in Nd : CaF2 markedly suppressed the quenching effect and improved the fluorescence quantum efficiency and emission spectra. With a fiber-coupled laser diode as the pump source, the continuous wave tuning range covering from 1042 to 1076 nm was realized, while the mode-locked operation generated 264 fs pulses with an average output power of 180 mW at a repetition rate of 85 MHz. The experimental results show that the Nd, Y-codoped CaF2 disordered crystal has potential in a new generation diode-pumped high repetition rate chirped pulse amplifier.
[Show abstract][Hide abstract] ABSTRACT: We experimentally prove the broad emission band of Nd:LGS disordered crystal and demonstrate a diode-pumped passively mode-locked femtosecond Nd-doped La3Ga5SiO14 (Nd:LGS) laser for the first time. With a birefringent filter inserted into the cavity, the tunable continuous wave (CW) laser of over 60 nm from 1045.2 nm to 1105.3 nm is achieved, which is the widest tuning range with Nd-doped crystals to our knowledge. Further in mode-locked operation, femtosecond pulses with pulse duration of 381 fs, average output power of 75 mW and repetition rate of 134.4 MHz are obtained at the central wavelength of 1066 nm. It is suitable to be a compact seed for femtosecond laser amplifiers.
[Show abstract][Hide abstract] ABSTRACT: We demonstrated the first low-threshold mode-locked Ti:sapphire oscillator pumped by a 488 nm fiber laser. Laser pulses as short as 8.2 fs with a bandwidth wider than 400 nm at a repetition rate of 148 MHz were generated under a pump power as low as 504 mW. Using a 0.5% output coupler, we further realized a 280 mW threshold power for mode-locking operation.
[Show abstract][Hide abstract] ABSTRACT: We experimentally demonstrated a stable diode-pumped Kerr-lens mode-locking femtosecond laser with a Yb3+-doped yttrium lanthanum oxide ceramic. Pulses as short as 85 fs at a central wavelength of 1074.5 nm were obtained at a repetition rate of 118 MHz. The average output power was 80 mW under a 4 W diode pump power. To the best of our knowledge, this is the first demonstration of a Kerr-lens mode-locked operation in a Yb3+-doped yttrium lanthanum oxide ceramic laser with a sub-100 fs pulse width.
[Show abstract][Hide abstract] ABSTRACT: An efficient femtosecond mode-locked laser using Nd and Y-codoped SrF2 crystal as the gain medium is presented in this letter. A 332 fs pulse centered at 1057 nm with a repetition rate of 89.8 MHz, a spectral width of 4.3 nm, and a mode-locked output power of up to 395 mW has been obtained under 1 W pump power, corresponding to an optical-to-optical efficiency of 39.5% and a slope efficiency of 69%. To the best of our knowledge, this is the highest optical efficiency in femtosecond Nd-doped crystal lasers.
[Show abstract][Hide abstract] ABSTRACT: A stable diode pumped Kerr-lens mode-locked (KLM) Yb:LuYSiO5 (Yb: LYSO) laser of generating 61 fs pulses at a central wavelength of 1055.4 nm is experimentally demonstrated. This is, to the best of our knowledge, the first demonstration of femtosecond KLM operation in Yb:LYSO laser, and it is believed that 61 fs is the shortest pulse duration ever produced from an Yb-doped orthosilicate laser. The average output power of the mode-locked laser is 40 mW and the repetition rate is 113 MHz. (C) 2014 Optical Society of America
[Show abstract][Hide abstract] ABSTRACT: We report a diode-pumped Yb:LYSO laser with a SESAM for mode-locking. Pulse with duration as short as 61 fs was obtained at repetition rate of 113 MHz. The average output power was 40 mW.
[Show abstract][Hide abstract] ABSTRACT: Pulses as short as 73-fs were generated from a Kerr-lens mode-locked Yb:YCa4O(BO3)3 laser at 1043 nm. To the best of our knowledge, this is the first demonstration of a Kerr-lens mode-locked Yb:YCa4O(BO3)3 laser.
[Show abstract][Hide abstract] ABSTRACT: A femtosecond OPA system for mid-infrared ultrafast laser is established. Pulse energy of 17-μJ is obtained from SiC crystal at central wavelength of 3.75-μm, which proves SiC an ideal nonlinear crystal for mid-infrared pulse generation.
[Show abstract][Hide abstract] ABSTRACT: The proton spectral and angular distributions simultaneously within the target normal direction and laser propagation direction by using an angle-resolved proton energy spectrometer are studied. For the protons generated in the interactions of 100 fs, 800 nm laser pulses with aluminum foil targets, the deviations of proton beam centers of different energies from the target normal direction towards the laser propagation direction are different. This is probably because of the toroidal magnetic fields generated at the rear target surface, which deflect protons transversely. As a result, protons in low energy range have large deviation angles, protons in middle energy range have the smallest deviation angles, while protons in high energy tail have large deviation angles.
[Show abstract][Hide abstract] ABSTRACT: We report a new nonlinear crystal, Ba<sub>1-x</sub>B<sub>2-y-z</sub>O<sub>4</sub>Si<sub>x</sub>Al<sub>y</sub>Ga<sub>z</sub>, and employ it to a compact 1 kHz single-longitudinal-mode Ti:Sapphire master oscillator power amplifier system for fourth harmonic generation. A maximum output power of 130 mW is obtained in the tunable range of 195-205 nm with linewidth of less than 0.1 pm.
[Show abstract][Hide abstract] ABSTRACT: We report a new nonlinear crystal, Ba1−xB2−y−zO4SixAlyGaz, and employ it to a compact 1 kHz single-longitudinal-mode Ti:Sapphire master oscillator power amplifier system for fourth harmonic generation. A maximum output power of 130 mW is obtained in the tunable range of 195–205 nm with linewidth of less than 0.1 pm.
[Show abstract][Hide abstract] ABSTRACT: We demonstrated a 100 TW-class femtosecond Ti: sapphire laser running at
repetition rate of 0.1 Hz by adding a stage amplifier in the 20 TW/10 Hz
laser facility (XL-II). Pumping the new stage amplifier with the 25 J
green Nd:glass laser, we successfully upgraded the laser energy to 3.4 J
with duration of 29 fs, corresponding to a peak power of 117 TW.
The European Physical Journal Conferences 11/2013; 59:07005-. DOI:10.1051/epjconf/20135907005
[Show abstract][Hide abstract] ABSTRACT: A high-stability and high-efficiency ring Ti:sapphire regenerative amplifier is demonstrated based on a double-gating pulse picker at a repetition rate of 1 kHz. Pulse energy up to 5.7 mJ is obtained using a pump energy of 20.0 mJ at 527 nm, corresponding to a relatively high slope efficiency of 30.3%. After a grating compressor, the laser pulse is compressed to 37.2 fs with an energy of 4.1 mJ. The beam quality factors M<sup>2</sup> are 1.4 and 1.3 in tangential and sagittal directions, respectively. The measured root mean square energy stability is better than 0.31% over an 11 h period.
[Show abstract][Hide abstract] ABSTRACT: A high contrast 1053nm femtosecond laser pulse with free background is demonstrated based on non-collinear optical-parametric amplification (NOPA). By permuting the signal and idler in two stages of NOPAs, 48.2 fs, 62 mu J laser pulse at 1053nm with contrast ratio of 2.3 x 10(-11) is obtained within the time scale of sub-5 ps. The beam quality factors M-2 for tangential and sagittal directions are 1.59 and 1.30, respectively. This work not only proves a feasible way to generate a clean femtosecond laser pulse but can also be employed as an ideal frontend for ultrashort ultrahigh intensity Nd:glass-based laser systems.
Lasers and Electro-Optics Pacific Rim (CLEO-PR), 2013 Conference on; 01/2013
[Show abstract][Hide abstract] ABSTRACT: A mode-locked Nd3+:LGS laser of running with femtosecond pulse was demonstrated. By using SF10 prism pair for dispersion compensation, 278 fs transform-limited pulse trains at the central wavelength of 1084 nm have been obtained.
Lasers and Electro-Optics Pacific Rim (CLEO-PR), 2013 Conference on; 01/2013
[Show abstract][Hide abstract] ABSTRACT: We report the first demonstration of femtosecond operation in a diode-pumped Yb-doped GdYSiO<sub>5</sub> (Yb:GYSO) laser. With a semiconductor saturable absorber mirror for passive mode locking and a pair of SF6 prisms for intracavity dispersion compensation, we realized stable passive mode locking with the new Yb-doped laser material. Femtosecond pulses as short as 324 fs were obtained at the central wavelength of 1091 nm. The maximum average power is 450 mW for an absorbed pump power of 2.8 W, with a slope efficiency of 18.5% and a pulse repetition frequency of 80.1 MHz.
[Show abstract][Hide abstract] ABSTRACT: We demonstrate a high energy picosecond optical parametric generation and amplification (OPA) system in the visible range based on two type-I phase matched β-barium borate crystals, in a walk-off compensating geometry. The second harmonic of a two-stage 60 ps Ti:sapphire laser amplifier at 10 Hz repetition rate serves as the pump. The signal is continuously tunable from 460 to 750 nm, which covers most of the visible range. The corresponding tuning range in the idler branch is from 0.86 to 3.07 μm. At a pumping energy of 110 mJ per pulse, the signal pulse energy is at 20 mJ class for most of the tuning wavelength in the OPA stage, and reaches a maximum of 33 mJ at 710 nm, corresponding to a conversion efficiency of ~ 30%.
[Show abstract][Hide abstract] ABSTRACT: A powerful terahertz (THz) pulse was produced by a p-polarized, 70 fs, 800 nm laser interacting with solid targets at an incident angle of 45°. The polarization of the THz emission was measured out of the laser incident plane. The results showed that it was linearly polarized. We established a surface current model to explain this phenomenon, assuming that the transient current moving along the plasma surface was responsible for the generation of the THz emission. The model expectation and the experimental result were in good agreement.