![]() In this thesis we have built a high energy pulsed parametric light source at 2100 nm, a wavelength that enables one to generate soft-x-ray photons with energies exceeding 300 eV through phase-matched HHG and further demonstrated HHG cutoff extension up to 190 eV in Argon, when compared to HHG from 800 nm pulses.When doing HHG, in order to restrict the soft-X-ray emission to a single isolated attosecond pulse one needs to employ a gating technique. This has implications for High harmonic generation (HHG) - the longer the wavelength of this field, the higher the energy of the generated photons. The scaling of strong field processes such as electron acceleration highly depends on the period or wavelength of the driving electrical field. Additionally, numerical simulations suggest that the nonlinear propagation dynamics induce self-compression, possibly leading to single-cycle pulses. This source has high repetition rate (100 kHz), high spectral density and absolute carrier-envelope phase stability. In this thesis a light source with more than 3 octaves (450-4500 nm) has been developed through filamentation of intense mid-IR pulses in solids. It follows that with the correct electric field shape, one could control and manipulate matter in new and interesting ways.In this thesis we have dedicated ourselves to the creation and characterisation of intense, few-cycle pulsed sources of light, using several different approaches. This implies that by focusing these pulses into matter one can destroy chemical bonds, free the electrons from the influence of the atom's nucleus and even further accelerate these particles away from the interaction region. When focused on a minuscule spot, the electric field oscillations of this wave would have amplitudes greatly surpassing the electric fields that bind electrons to atoms, or even atoms together in molecules. If such pulse would have a very modest energy (e.g., a Joule), it would have a peak power approaching the PetaWatt - several orders of magnitude more than the total energy production on earth at a given time. ![]() For example, by compressing in time all the colours in sunlight one would generate a light pulse with just a few femtoseconds duration. If one were to overlap all the frequencies in a temporally coherent beam of light, one could generate an extremely short and powerful pulse. ![]() This lack of a clear spatio-temporal structure in naturally occurring light - coherence - limits what can be done with it. However, As the scale over which the colour changes is spatially too small and temporarily too rapid to be resolved by the human eye we perceive it as a smooth white beam. What one would perceive as a smooth beam of white light is actually an ever changing pattern of colours. the sun), despite its serene and directional appearance, exists in a state of ever changing disorder. Not all light is equal, however - the light that we normally interact on a daily basis (e.g. For example, light is increasingly more important as a tool for humanity. Devising new tools that expand our capabilities to sense and manipulate the world enables much of the scientific and technological progress around us.
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