The high harmonic generation(HHG)by few-cycle laser pulses is essential for research in strong-field solid-state physics.Through comparison of high harmonic spectra of solids generated by laser pulses with varying dur...The high harmonic generation(HHG)by few-cycle laser pulses is essential for research in strong-field solid-state physics.Through comparison of high harmonic spectra of solids generated by laser pulses with varying durations,we discovered that lasers with good dispersion compensation are capable of producing a broad spectrum of high harmonics.As the pulse duration is further compressed,several interference peaks appear in the broad spectrum.Moreover,we conducted simulations using the semiconductor Bloch equation,considering the effect of Berry curvature,to better understand this process.Our work provides a valuable approach for studying HHG by few-cycle laser pulses in solid materials,expanding the application of HHG in attosecond physics.展开更多
High-order harmonic generation(HHG) driven by two non-collinear beams including a fundamental and its weak second harmonic is numerically studied. The interference of harmonics from adjacent electron quantum paths is ...High-order harmonic generation(HHG) driven by two non-collinear beams including a fundamental and its weak second harmonic is numerically studied. The interference of harmonics from adjacent electron quantum paths is found to be dependent on the relative delay of the driving pulse, and the dependences are different for different harmonic orders.This frequency dependence of the interference is attributed to the spatial frequency chirp in the HHG beam resulting from the harmonic dipole phase, which in turn provides a potential way to gain an insight into the generation of high-order harmonics. As an example, the intensity dependent dipole phase coefficient α is retrieved from the interference fringe.展开更多
Isolated attosecond extreme-ultraviolate(XUV)pulses are generated based on high-harmonic-generation from a neon gas cell driven by carrier-envelope phase stabilized sub-5-fs Ti:sapphire laser pulses at repetition rate...Isolated attosecond extreme-ultraviolate(XUV)pulses are generated based on high-harmonic-generation from a neon gas cell driven by carrier-envelope phase stabilized sub-5-fs Ti:sapphire laser pulses at repetition rate of 1kHz.Temporal characterization of isolated attosecond XUV pulses is demonstrated to be 160-attosecond by attosecond streaking spectroscopy.The development of attosecond source and streaking spectroscopy will allow scientists to explore the electron dynamics in matter.展开更多
Isolated attosecond pulses(IAPs)are generated via applying amplitude gating on high-order harmonic generation driven by carrier-envelope phase stabilized 5.2 fs pulses with 0.5 mJ pulse energy at 770 nm central wavele...Isolated attosecond pulses(IAPs)are generated via applying amplitude gating on high-order harmonic generation driven by carrier-envelope phase stabilized 5.2 fs pulses with 0.5 mJ pulse energy at 770 nm central wavelength at the Synergetic Extreme Condition User Facility.A continuum ranging from 70 to 100 eV that supports sub-100-attosecond pulse is extracted by Zr foil and Mo/Si multilayer mirror.We demonstrate the characterization of the IAP.The retrieved pulse duration is 86attoseconds.The developed attosecond laser beamline with repetition rate up to 10 kHz is available for users to conduct attosecond photoelectron spectroscopy researches with a capability of coincidence measurement.展开更多
基金Project supported by the National Natural Science Foundation of China(Grant Nos.91850209 and 11974416)。
文摘The high harmonic generation(HHG)by few-cycle laser pulses is essential for research in strong-field solid-state physics.Through comparison of high harmonic spectra of solids generated by laser pulses with varying durations,we discovered that lasers with good dispersion compensation are capable of producing a broad spectrum of high harmonics.As the pulse duration is further compressed,several interference peaks appear in the broad spectrum.Moreover,we conducted simulations using the semiconductor Bloch equation,considering the effect of Berry curvature,to better understand this process.Our work provides a valuable approach for studying HHG by few-cycle laser pulses in solid materials,expanding the application of HHG in attosecond physics.
基金Project supported by the National Key Basic Research Program of China(Grant Nos.2013CB922401 and 2013CB922402)the National Key Scientific Instrument and Equipment Development Projects,China(Grant No.2012YQ12004704)+1 种基金the National Natural Science Foundation of China(Grant No.11374356)the International Joint Research Program of National Natural Science Foundation of China(Grant No.61210017)
文摘High-order harmonic generation(HHG) driven by two non-collinear beams including a fundamental and its weak second harmonic is numerically studied. The interference of harmonics from adjacent electron quantum paths is found to be dependent on the relative delay of the driving pulse, and the dependences are different for different harmonic orders.This frequency dependence of the interference is attributed to the spatial frequency chirp in the HHG beam resulting from the harmonic dipole phase, which in turn provides a potential way to gain an insight into the generation of high-order harmonics. As an example, the intensity dependent dipole phase coefficient α is retrieved from the interference fringe.
基金Supported by the National Basic Research Program of China(973 Program)under Grant No 2013CB922402the Instrument Developing Project of the Chinese Academy of Sciences under Grant No 2010004,and the National Natural Science Foundation of China under Grant No 11074298.
文摘Isolated attosecond extreme-ultraviolate(XUV)pulses are generated based on high-harmonic-generation from a neon gas cell driven by carrier-envelope phase stabilized sub-5-fs Ti:sapphire laser pulses at repetition rate of 1kHz.Temporal characterization of isolated attosecond XUV pulses is demonstrated to be 160-attosecond by attosecond streaking spectroscopy.The development of attosecond source and streaking spectroscopy will allow scientists to explore the electron dynamics in matter.
基金Supported by the National Basic Research Program of China under Grant Nos 2013CB922401 and 2013CB922402, the National Natural Science Foundation of China under Grant No 11074298, and the Instrument Developing Project of the Chinese Academy of Sciences under Grant No 2010004.
基金supported by the Synergic Extreme Condition User Facility(SECUF),the National Natural Science Foundation of China(Nos.91850209,12034020,92150103,61690221,and 12174435)the National Key R&D Program of China(Nos.2022YFA1604200 and 2017YFB0405202)。
文摘Isolated attosecond pulses(IAPs)are generated via applying amplitude gating on high-order harmonic generation driven by carrier-envelope phase stabilized 5.2 fs pulses with 0.5 mJ pulse energy at 770 nm central wavelength at the Synergetic Extreme Condition User Facility.A continuum ranging from 70 to 100 eV that supports sub-100-attosecond pulse is extracted by Zr foil and Mo/Si multilayer mirror.We demonstrate the characterization of the IAP.The retrieved pulse duration is 86attoseconds.The developed attosecond laser beamline with repetition rate up to 10 kHz is available for users to conduct attosecond photoelectron spectroscopy researches with a capability of coincidence measurement.