Possibility of self-similar pulse evolution in a Ti:sapphire laser (original) (raw)
Related papers
Pulse evolution dynamics of a femtosecond passively mode-locked Ti:sapphire laser
Optics Letters, 1992
The pulse-formation process in a femtosecond passively mode-locked Ti:sapphire laser with a saturable absorber is investigated. The time to reach the steady state is -200 As. The formation time dependence on the dye concentration and the coincidence of the steady-state pulse width with the self-mode-locked state without a saturable absorber indicate that the function of the saturable absorber is mainly to induce the initial modulation and to shorten the pulse-formation time.
Nonlinear Effect of an Ultrashort Laser Pulse Propagation in Ti:Sapphire Crystal
Journal of Computational and Theoretical Nanoscience, 2009
Impact of such terms as third order dispersion, self-steepening and stimulated Raman scattering on evolution of ultrashort pulses is considered in detail. Under influence of these effects, pulse did not maintain its initial shape in the case of the silica fiber. Pulse splits into constituents, its spectrum also evolving into several bands which are known as optical shock and self-frequency shift phenomena. We concluded that when the input peak power is large enough, dynamics of pulse splitting will be complicated. We propose in this article, a new generation of the fiber type; the Ti:sapphire crystal fiber which is able to solve these problems of writings before. Our numerical simulations were in good agreement with the Ti:sapphire crystal fiber One basing itself on the resolution of the nonlinear Schrödinger equation.
Spatial–temporal analysis of the self-mode-locked Ti: sapphire laser
Journal of the Optical Society of America B, 1993
We employ our extended spatial-temporal matrices to analyze the Ti: sapphire self-mode-locked laser. Our results agree with previously reported experimental work and give us a deeper understanding of the way this laser functions. We found the pulse-shaping mechanism to be essentially solitonlike; the role of the aperture is to discriminate against cw operation. We also study the buildup of the pulse starting from a fluctuation.
Self-mode-locking of Ti:sapphire lasers: a matrix formalism
Optics Letters, 1992
An extension of the ray-pulse matrix formalism is presented that includes self-phase-modulation, self-focusing, bandwidth limitations, and Gaussian apertures. With this more complete set of matrices it is shown how selfmode-locked lasers can be modeled and how the different pulse-shaping mechanisms interact in order to provide a stable femtosecond output.
Applied Physics Letters, 1999
We have demonstrated a high-average-power, mode-locked Ti:sapphire laser with an intracavity continuous-wave amplification scheme. The laser generated 150 fs pulses with 3.4 W average power at a repetition rate of 79 MHz. This simple amplification scheme can be applied for the power scaling of other lasers. Some years ago, there was a breakthrough in modelocking techniques for solid-state lasers. 1,2 Applying the techniques utilizing Kerr-type nonlinearity, most solid-state lasers could be mode-locked down to the femtosecond region. Shortly after that, amplification of these ultrashort pulses to gigawatt peak power was demonstrated 3 using chirped pulse amplification. 4 However, this kind of amplification reduces the pulse repetition rate to the order of ϳ100 kHz, and there is often a loss of time resolution in the final pulse. A higher repetition rate results in much smaller pulse fluctuation and excellent experimental signal-to-noise ratios. Much progress has been made in extending the spectral range of high-repetition-rate femtosecond pulses throughout the ultraviolet, visible, and infrared ͑IR͒ regions by using frequency conversion in crystals. The ϳ80 MHz, 2-W-level femtosecond Ti:sapphire lasers have been used for fourth harmonic generation near 200 nm, 5 visible range, 6-8 and IR range 9 optical parametric oscillator and coherent THzradiation from semiconductors. 10 If there is some scheme to scale the power of high-repetition-rate femtosecond lasers, there will be interesting applications for the various wavelength conversion techniques mentioned above. The requirement for the average power has been one of the most important factors especially for these lasers used as pump sources of THz-radiation from InAs in a magnetic field, 10 because THz-radiation power is known to have a quadratic dependence on the excitation high-repetition-rate femtosecond laser average power. Also, the average power is important for the intracavity doubling of a femtosecond laser. 11 In contrast to continuous wave ͑cw͒ high-average-power lasers, the power scaling of the high-repetition-rate femtosecond modelocked lasers is difficult. This is partly due to the limitation of available power from the pumping source. The major problem was the difficulty of maintaining the beam quality good enough for mode locking and balancing the thermal lens effect and Kerr lens effect at the same time. With these limitations, the output average power of femtosecond modelocked lasers has been limited to the 2 W level. In this letter, we describe a high-repetition-rate ͑79 MHz͒, highaverage-power ͑3.4 W͒, mode-locked femtosecond Ti:sapphire laser realized by applying an intracavity cwamplification scheme.
Dispersion-managed mode-locking dynamics in a Ti:sapphire laser
Physical Review A, 2006
We present what is to our knowledge the most complete 1-D numerical analysis of the evolution and the propagation dynamics of an ultrashort laser pulse in a Ti:Sapphire laser oscillator. This study confirms the dispersion managed model of mode-locking, and emphasizes the role of the Kerr nonlinearity in generating mode-locked spectra with a smooth and well − behaved spectral phase. A very good agreement with preliminary experimental measurements is found.
2011
The correlation between mode locked pulse and its corresponding femtosecond generation are reported. A non-self starting Ti:sapphire laser was aligned to induce mode locked pulse. The cavity length was adjusted in the range from 104 to 105 mm to stabilize the mode locked pulse train. The mode locked pulse was recorded via high speed oscilloscope at various cavity lengths in the stability region. The corresponding femtosecond pulse generation was simultaneously measured via autocorrelator. This is referred as conjugate method. The result shows that the femtosecond pulse found to be having a linear relationship with mode locked pulse with the conversion efficiency achieved up to 8%.
Continuous-wave mode-locked Ti:sapphire laser focusable to 5 × 10^13 W/cm^2
Optics Letters, 1998
Generation of sub-10-fs pulses with an average power of 1 W and a peak of 1.5 MW from a Kerr-lens mode-locked mirror-dispersion-controlled Ti:sapphire laser is demonstrated. A specially designed lens triplet focuses the output of this compact all-solid-state source to a peak intensity in excess of 5 3 10 13 W͞cm 2 . Nonperturbative nonlinear optics is now becoming feasible by use of the output of a cw mode-locked laser.
Self-similar pulse evolution in an all-normal-dispersion laser
Physical Review A, 2010
Parabolic amplifier similaritons are observed inside a normal-dispersion laser. The self-similar pulse is a local nonlinear attractor in the gain segment of the oscillator. The evolution in the laser exhibits large (20 times) spectral breathing, and the pulse chirp is less than the group-velocity dispersion of the cavity. All of these features are consistent with numerical simulations. The amplifier similariton evolution also yields practical features such as parabolic output pulses with high energies, and the shortest pulses to date from a normal-dispersion laser.