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
As ultrafast laser technology advances towards ever higher peak and average powers,generating sub-50 fs pulses from laser architectures that exhibit best power-scaling capabilities remains a major challenge.Here,we pr...As ultrafast laser technology advances towards ever higher peak and average powers,generating sub-50 fs pulses from laser architectures that exhibit best power-scaling capabilities remains a major challenge.Here,we present a very compact and highly robust method to compress 1.24 ps pulses to 39fs by means of only a single spectral broadening stage which neither requires vacuum parts nor custom-made optics.Our approach is based on the hybridization of the multiplate continuum and.the multipass cell spectral broadening techniques.Their combination leads to significantly higher spectral broadening factors in bulk material than what has been reported from either method alone.Moreover,our approach efficiently suppresses adverse features of single-pass bulk spectral broadening.We use a burst-mode Yb:YAG laser emitting pulses with 80 MW peak power that are enhanced to more than 1 GW after postcompression.With only 0.19%rms pulse-to-pulse energy fluctuations,the technique exhibits excellent stability.Furthermore,we have measured state-of-the-art spectral-spatial homogeneity and good beam quality of M^(2)=1.2 up to a spectral broadening factor of 30.Due to the method's simplicity,compactness,and scalability,it is highly attractive for turning a picosecond laser into an ultrafast light source that generates pulses of only a few tens of femtoseconds duration.展开更多
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As ultrafast laser technology advances towards ever higher peak and average powers,generating sub-50 fs pulses from laser architectures that exhibit best power-scaling capabilities remains a major challenge.Here,we present a very compact and highly robust method to compress 1.24 ps pulses to 39fs by means of only a single spectral broadening stage which neither requires vacuum parts nor custom-made optics.Our approach is based on the hybridization of the multiplate continuum and.the multipass cell spectral broadening techniques.Their combination leads to significantly higher spectral broadening factors in bulk material than what has been reported from either method alone.Moreover,our approach efficiently suppresses adverse features of single-pass bulk spectral broadening.We use a burst-mode Yb:YAG laser emitting pulses with 80 MW peak power that are enhanced to more than 1 GW after postcompression.With only 0.19%rms pulse-to-pulse energy fluctuations,the technique exhibits excellent stability.Furthermore,we have measured state-of-the-art spectral-spatial homogeneity and good beam quality of M^(2)=1.2 up to a spectral broadening factor of 30.Due to the method's simplicity,compactness,and scalability,it is highly attractive for turning a picosecond laser into an ultrafast light source that generates pulses of only a few tens of femtoseconds duration.
