The Reflection Of Electron Motion In Atomic Systems

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Electron motion in atomic systems, which happens on timescales of attoseconds, is at the heart of all phenomena in nature (except for nuclear processes). Electron motion is responsible for the emission of light and photosynthesis in plants. Electron motion across biological molecules transports information in our nerves and is involved in processing this information in our brains. Moreover, the valence electrons are responsible for binding atoms to form molecules. The structural change of molecule is triggered by motion of electrons in the chemical bonds. Controlling this fast electron motion, in turn, allows to control the molecular structure change. Additionally, the ability to take snapshots of the electron motion dynamics will improve our …show more content…
In the first part of my Ph.D. training, I have designed and built the prototype light field synthesizer (Fig. 1a), including all the technical developments required to generate and demonstrate the first synthesized sub-optical cycle laser pulses (~2fs) (generation & metrology) with attosecond resolution, Science 334, 195, (2011). The attained resolution made possible the demonstration of the first pump-probe experiment with attosecond resolution and has enabled the real-time observation of the valence electron motion and light-field-induced stark shift in krypton …show more content…
I have extended the light filed sculpting over more than two octaves in the visible frequency and flanking ranges to generate the first optical attosecond pulse (OAP) (carried at central wavelength =530 nm and FWHM of instantaneous intensity (380as), Fig. 1b). This is a new tool in the science of light that combines the energy range and the power of few-cycle pulses and the temporal resolution of a EUV attosecond pulses. The ability to control the field of the OAP offers direct drive and control of bound electrons motion in atoms, molecules, and nanostructures with attosecond precision. I have used the field-controlled OAP to reveal the nonlinear response time of bound electrons in a krypton atom which is in the order of hundred attoseconds (Nature, In Revision). Also, OAP has been used to generate extreme ultraviolet radiation from solids, paving the way for developing extreme ultraviolet solid-state Photonics (Nature 521, 498

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