I.T. Sorokina

Directly diode-pumped Kerr-lens mode-locked Cr^4^+:YAG laser

A directly diode-pumped Kerr-lens mode-locked Cr4+:YAG laser is demonstrated for what is to our knowledge the first time. Pulses as short as 65 fs with up to 30 mW of average output power, at a central wavelength of 1569 nm, were obtained at a repetition rate of 100 MHz. Low-loss chirped mirrors have been used for dispersion compensation up to the third order. Comparison with an Yb-fiber-pumped configuration shows good prospects for improvement.

Room-temperature lasing in nanocrystalline Cr 2+ :ZnSe random laser

We report the first room-temperature pulsed lasing around 2.4 μm from the single-crystalline Cr2+:ZnSe powder active medium with particle sizes varying from hundreds of nanometers to micrometers. Pump energy density at laser threshold of ~34 mJ/cm2 has been observed.

Mode-locked ceramic Cr 2+ :ZnSe laser

We present the results of mode-locking of the ceramic Cr2+:ZnSe laser at 2.5 μm pumped by a diode-pumped Nd:YVO4 -Co2+:MgF2 laser and provide a comparison between the mode-locked ceramic and single crystalline Cr:ZnSe lasers.

Directly diode-pumped femtosecond Cr 4+ :YAG laser

In this work we demonstrate the first passive modelocking of a directly diode-pumped Cr4+:YAG laser with semiconductor saturable absorber mirror (SESAM) as a starting mechanism generating stable near transform-limited pulses at down to 62 fs pulse duration at 15 mW output power.

Tunable diode-pumped continuous-wave single crystal and ceramic Cr/sup 2+/:ZnSe lasers

We report the first broadly tunable over 350 nm diode-pumped cw room-temperature crystalline Cr:ZnSe laser, delivering 65 mW, as well as the first diode-pumped ceramic Cr:ZnSe laser, delivering 20 mW.

Energy-scalable mid-infrared femtosecond oscillators: positive vs. negative dispersion regimes

In this work we analyze the stability of an energy-scalable Cr:ZnSe oscillator and compare the limits of energy scalability in the positive-and negative-dispersion regimes.The stability analysis is based on the comprehensive numerical simulations within the cubic-quintic nonlinear complex Ginzburg-Landau model.

Prospects of multi-GHz femtosecond operation of a diode-pumped Cr/sup 4+/:YAG laser

In this paper we investigate the possibility of the stable CW mode locking of a Cr:YAG microchip laser with the InGaAs/lnP quantum-well SESAM. The integrated design does not leave many control parameters and our analysis is aimed at optimization of the SESAMs relaxation kinetics, using the numerical model. We analyze the complete temporal dynamics of the two-element micro-chip oscillator with 0.5 cm cavity, 1% output coupler and 100 /spl mu/m beam radius. It was found that, in contrast to the oscillators with /spl sim/100 MHz pulse repetition rate, the presence of the slow loss relaxation component is necessary for the pulse stabilization.

Diode-pumped self-starting few optical cycle pulse generation at 1.5 /spl mu/m

Two ways to generate self-starting few optical cycle pulses around 1.5 /spl mu/m using a compact diode-pumped Cr:YAG laser (purely Kerr-lens mode-locking and SESAM assisted mode-locking) are reviewed. The shortest reported at 1.5 /spl mu/m transform-limited 27 fs (five optical cycles) pulses could be obtained using a novel hybrid dielectric-InGaAs/InP SESAM.

Mechanisms of the few-optical cycle pulse spectrum shift in Cr/sup 4+/:YAG laser

In this paper, we analyzed various possible causes and attribute the pulse down-frequency shift and its spectral extra-broadening in Cr/sup 4+/:YAG laser to the combined action of the intracavity third-order dispersion (TOD) and the stimulated Raman scattering (SRS) within an active medium. The results of the numerical simulations are in agreement with the experimental data obtained in the Kerr-lens mode-locked Cr/sup 4+/:YAG laser providing five optical cycle pulse generation. We showed that the pulse spectrum extra-broadening noticeably exceeding the gain bandwidth is analogous to the spectral continuum generation in fibers in the vicinity of the zero group-delay dispersion.

SESAM mode-locked diode-pumped femtosecond Cr:YAG laser

In this paper we report the development of the compact directly diode-pumped as well as Yb-fiber pumped broadband femtosecond Cr/sup 4+/:YAG laser, operating around 1.5 /spl mu/m. The laser is mode-locked using the novel hybrid InGaAs-InP based semiconductor saturable absorber mirror (SESAM) combined with the broadband dielectric mirror and generating down to sub-50 fs transform-limited pulses. The advantage of SESAM mode-locking over the pure Kerr-lens modelocking is the absence of a CW component. The SESAM and the prisms impose relatively high insertion losses.