The objective of this work was to investigate the possibility of taper angle correction in cutting of complex micro-mechanical contours using a TruMicro ultra-short pulse laser in combination with the SCANLAB precSYS ...The objective of this work was to investigate the possibility of taper angle correction in cutting of complex micro-mechanical contours using a TruMicro ultra-short pulse laser in combination with the SCANLAB precSYS micro machining sub system. In a first step, the influence of the process parameters on the kerftaper angle of metallic alloys was systematically investigated without beam inclination. A set of base parameters was derived for the subsequent investigations. In a second step, the kerftaper angle was controlled by static beam inclination. In a third step, the same optics was used in its dynamic precession mode to fabricate micro-mechanical components of complex contours with perpendicular 0~ taper angles. It was found that taper angle adjustments of up to 7.5~ are possible with the used setup for cutting applications. Taper angle control is possible both in the static beam inclination mode and in the dynamic precession mode. The static mode could be interesting for contours with sharp inner radii and for achieving faster cutting times similar to results with fixed optics, but would require excellent synchronization of beam inclination and axis motion. The dynamic precession mode would allow an easier integration of the optics into a laser machine but will result in longer cutting times and limitations with respect to achievable inner radii.展开更多
The demand for and usage of broadband coherent mid-infrared sources,such as those provided by synchrotron facilities,are growing.Since most organic molecules exhibit characteristic vibrational modes in the wavelength ...The demand for and usage of broadband coherent mid-infrared sources,such as those provided by synchrotron facilities,are growing.Since most organic molecules exhibit characteristic vibrational modes in the wavelength range between 500 and 4000 cm^(−1),such broadband coherent sources enable micro-or even nano-spectroscopic applications at or below the diffraction limit with a high signal-to-noise ratio1–3.These techniques have been applied in diverse fields ranging from life sciences,material analysis,and time-resolved spectroscopy.Here we demonstrate a broadband,coherent and intrinsically carrier-envelope-phase-stable source with a spectrum spanning from 500 to 2250 cm^(−1)(−30 dB)at an average power of 24mW and a repetition rate of 77 MHz.This performance is enabled by the first mode-locked thin-disk oscillator operating at 2μm wavelength,providing a tenfold increase in average power over femtosecond oscillators previously demonstrated in this wavelength range4.Multi-octave spectral coverage from this compact and power-scalable system opens up a range of time-and frequency-domain spectroscopic applications.展开更多
SwissFEL is a compact,high-brilliance,soft and hard X-ray free electron laser(FEL)facility that started user operation in 2019.The facility is composed of two parallel beam lines seeded by a common linear accelerator(...SwissFEL is a compact,high-brilliance,soft and hard X-ray free electron laser(FEL)facility that started user operation in 2019.The facility is composed of two parallel beam lines seeded by a common linear accelerator(LINAC),and a two-bunch photo-injector.For the injector,an innovative dual-photocathode laser scheme has been developed based on state-of-the-art ytterbium femtosecond laser systems.In this paper,we describe the performance of the Swiss FEL photocathode drive lasers(PCDLs),the pulse-shaping capabilities as well as the versatility of the systems,which allow many different modes of operation of Swiss FEL.The full control over the Swiss FEL electron bunch properties via the unique architecture of the PCDLs will enable in the future the advent of more-advanced FEL modes;these modes include,but are not restricted to,the generation of single or trains of sub-femtosecond FEL pulses,multi-color FEL and finally,the generation of fully coherent X-ray pulses via laser-based seeding.展开更多
文摘The objective of this work was to investigate the possibility of taper angle correction in cutting of complex micro-mechanical contours using a TruMicro ultra-short pulse laser in combination with the SCANLAB precSYS micro machining sub system. In a first step, the influence of the process parameters on the kerftaper angle of metallic alloys was systematically investigated without beam inclination. A set of base parameters was derived for the subsequent investigations. In a second step, the kerftaper angle was controlled by static beam inclination. In a third step, the same optics was used in its dynamic precession mode to fabricate micro-mechanical components of complex contours with perpendicular 0~ taper angles. It was found that taper angle adjustments of up to 7.5~ are possible with the used setup for cutting applications. Taper angle control is possible both in the static beam inclination mode and in the dynamic precession mode. The static mode could be interesting for contours with sharp inner radii and for achieving faster cutting times similar to results with fixed optics, but would require excellent synchronization of beam inclination and axis motion. The dynamic precession mode would allow an easier integration of the optics into a laser machine but will result in longer cutting times and limitations with respect to achievable inner radii.
基金supported by the Munich-Centre for Advanced Photonics(MAP)Center for Advanced Laser Applications(CALA).
文摘The demand for and usage of broadband coherent mid-infrared sources,such as those provided by synchrotron facilities,are growing.Since most organic molecules exhibit characteristic vibrational modes in the wavelength range between 500 and 4000 cm^(−1),such broadband coherent sources enable micro-or even nano-spectroscopic applications at or below the diffraction limit with a high signal-to-noise ratio1–3.These techniques have been applied in diverse fields ranging from life sciences,material analysis,and time-resolved spectroscopy.Here we demonstrate a broadband,coherent and intrinsically carrier-envelope-phase-stable source with a spectrum spanning from 500 to 2250 cm^(−1)(−30 dB)at an average power of 24mW and a repetition rate of 77 MHz.This performance is enabled by the first mode-locked thin-disk oscillator operating at 2μm wavelength,providing a tenfold increase in average power over femtosecond oscillators previously demonstrated in this wavelength range4.Multi-octave spectral coverage from this compact and power-scalable system opens up a range of time-and frequency-domain spectroscopic applications.
文摘SwissFEL is a compact,high-brilliance,soft and hard X-ray free electron laser(FEL)facility that started user operation in 2019.The facility is composed of two parallel beam lines seeded by a common linear accelerator(LINAC),and a two-bunch photo-injector.For the injector,an innovative dual-photocathode laser scheme has been developed based on state-of-the-art ytterbium femtosecond laser systems.In this paper,we describe the performance of the Swiss FEL photocathode drive lasers(PCDLs),the pulse-shaping capabilities as well as the versatility of the systems,which allow many different modes of operation of Swiss FEL.The full control over the Swiss FEL electron bunch properties via the unique architecture of the PCDLs will enable in the future the advent of more-advanced FEL modes;these modes include,but are not restricted to,the generation of single or trains of sub-femtosecond FEL pulses,multi-color FEL and finally,the generation of fully coherent X-ray pulses via laser-based seeding.
