[Show abstract][Hide abstract] ABSTRACT: Growth of strongly textured FeCO 3 thin films on substrates was achieved with ultrashort-pulsed laser deposi-tion using 810-nm, 46-fs ablation pulses. The crystallinity and composition were verified with X-ray diffraction and Raman spectroscopy. Using Mössbauer spectroscopy, it is shown that the deposited FeCO 3 thin films possess the film quality required for application in research of nuclear quantum optics. It is found that a relatively low substrate temperature is crucial for growing a strongly textured film of FeCO 3 while avoiding decomposition of FeCO 3 into Fe 2 O 3 and CO 2 . This supports the importance of the use of ultrashort-pulsed laser deposition in providing adatoms with high mobility for attaining good crystallinity. The sur-face morphology was characterized by surface profilometry, scanning electron microscopy and atomic force microscopy. It is found to be significantly affected by changing the ab-lation laser parameters, including laser fluence, pulse dura-tion, and on-target spot size. The results show that the peak deposition flux must be below approximately 0.03 nm/pulse in order to grow a flat film.
[Show abstract][Hide abstract] ABSTRACT: Sharp periodic enhancement of high-harmonic generation synchronized to prepulse-induced cluster vibration is observed. Tenfold enhancement of high-harmonic-generation efficiency is achieved by optimal selection of the prepulse-pump delay. This strong correlation between high-harmonic generation and cluster vibration also provides a new tool for studying the vibrational dynamics of nanometer atomic clusters.
[Show abstract][Hide abstract] ABSTRACT: Enhancement of high-harmonic-generation efficiency of a cluster jet by an order of magnitude is achieved at adequate prepulse-pump delays. This effect also allows characterization of the size and vibration dynamics of atom clusters.
Nonlinear Optics: Materials, Fundamentals and Applications; 07/2007