Coupled cavity modelocking of a Nd:YAG laser using second harmonic generation

Recently it has been demonstrated that intracavity second harmonic generation (SHG) In a Nd:YAG laser can lead to mode locking with pulse durations of ~ 100 ps at 532 nm. Other work has shown that nonlinear processes in an external coupled cavity can effectively mode lock a laser. These two mechanisms are combined to mode lock a Nd:YAG laser using SHG as the nonlinearity

Generation of ultrabright beams in high energy Nd:glass and KrF laser systems

The development of ultrabright lasers is progressing rapidly particularly in the direction of table-top-terawatt systems operating at high pulse repetition rate with relatively low pulse energy. The highest pulse energies and highest absolute powers are being generated by the adaptation of larger-scale high energy laser systems operating in single pulse mode. The maximum focused intensity from either type of laser is determined by the beam brightness B which can be expressed in units of Watts cm where P is the power, lambda the wavelength and S the Strehl ratio, quantifying the ratio of brightness in a beam with less than diffraction limited quality to that in a diffraction limited beam

Modelocking using mirrors with intensity dependant reflection coefficients

The steady state modelocking of a laser incorporating a mirror with an intensity dependent reflection coefficient is analysed The pulse length is determined by the balance between pulse stretching due to gain narrowing and pulse shortening due to the nonlinear mirror. The final pulse length can approach the limit set by the gain bandwidth of the active medium

Enhancement of the modulation depth of an active modelocker using an external cavity

An external cavity containing a standard active modelocker can result in enhanced modelocking of lasers. The pulse length reduction depends on the configuration chosen and can be as large as 50%

An interferometric measurement of the 1S-2S transition frequency in atomic hydrogen

SIGLEAvailable from British Library Document Supply Centre- DSC:D177279 / BLDSC - British Library Document Supply CentreGBUnited Kingdo

Numerical simulation of self starting of a modelocked laser with a nonlinear mirror based on second harmonic generation

A simple computer model of modelocking using an intracavity nonlinear mirror based on second harmonic generation has been constructed. Saturation of the gain medium is included. The model exhibits experimentally observed features such as a second harmonic conversion efficiency threshold before modelocking occurs. Self Q-switching and modelocking occurs for sufficiently large values of fluorescence lifetime. The model predicts that there is a narrow region above the modelocking threshold which allows steady state modelocking to occur even in long fluorescence lifetime materials

Coupled cavity modelocking using nonlinear amplitude modulators

A straightforward analysis of the process by which nonlinear amplitude modulators in coupled cavities can lead to enhanced mode-locking is presented. The application of the theory is demonstrated by using second-harmonic generation in an external cavity to mode-lock a Nd:YAG laser yielding 30 ps pulses in a Q-switched and mode-locked pulse train

Coupled cavity modelocking of a Nd:YAG laser using second harmonic generation

The modelocking of a Nd:YAG laser using second-harmonic generation in an external cavity as the only pulse shortening process is reported. The output of a long pulse Nd:YAG laser was simultaneously modelocked and Q-switched. The average pulse duration was 30-50 ps and the peak power was in the range 60-160 kW