Isolated attosecond pulse(IAP)generation usually involves the use of short-medium gas cells operated at high pressures.In contrast,long-medium schemes at low pressures are commonly perceived as inherently unsuitable f...Isolated attosecond pulse(IAP)generation usually involves the use of short-medium gas cells operated at high pressures.In contrast,long-medium schemes at low pressures are commonly perceived as inherently unsuitable for IAP generation due to the nonlinear phenomena that challenge favourable phase-matching conditions.Here we provide clear experimental evidence on the generation of isolated extreme-ultraviolet attosecond pulses in a semiinfinite gas cell,demonstrating the use of extended-medium geometries for effective production of IAPs.To gain a deeper understanding we develop a simulation method for high-order harmonic generation(HHG),which combines nonlinear propagation with macroscopic HHG solving the 3D time-dependent Schrödinger equation at the singleatom level.Our simulations reveal that the nonlinear spatio-temporal reshaping of the drivingfield,observed in the experiment as a bright plasma channel,acts as a self-regulating mechanism boosting the phase-matching conditions for the generation of IAPs.展开更多
Unraveling the exact nature of nonequilibrium and correlated interactions is paramount for continued progress in many areas of condensed matter science. Such insight is a prerequisite to develop an engineered approach...Unraveling the exact nature of nonequilibrium and correlated interactions is paramount for continued progress in many areas of condensed matter science. Such insight is a prerequisite to develop an engineered approach for smart materials with targeted properties designed to address standing needs such as efficient light harvesting, energy storage, or information processing. For this goal, it is critical to unravel the dynamics of the energy conversion processes between carriers in the earliest time scales of the excitation dynamics. We discuss the implementation and benefits of attosecond soft x-ray core-level spectroscopy up to photon energies of 600 eV for measurements in solid-state systems. In particular, we examine how the pairing between coherent spectral coverage and temporal resolution provides a powerful new insight into the quantum dynamic interactions that determine the macroscopic electronic and optical response. We highlight the different building blocks of the methodology and point out the important aspects for its application from condensed matter studies to materials as thin as 25 nm. Furthermore, we discuss the technological developments in the field of tabletop attosecond soft x-ray sources with time-resolved measurements at the near and extended edge simultaneously and investigate the exciting prospective of extending such technique to the study of 2-dimensional materials.展开更多
基金funding from the European Union’s Horizon 2020 research and innovation programme(grant agreement No 871161,IMPULSE)and European Research Council(ERC):ERC Synergy grant agreement no.
文摘Isolated attosecond pulse(IAP)generation usually involves the use of short-medium gas cells operated at high pressures.In contrast,long-medium schemes at low pressures are commonly perceived as inherently unsuitable for IAP generation due to the nonlinear phenomena that challenge favourable phase-matching conditions.Here we provide clear experimental evidence on the generation of isolated extreme-ultraviolet attosecond pulses in a semiinfinite gas cell,demonstrating the use of extended-medium geometries for effective production of IAPs.To gain a deeper understanding we develop a simulation method for high-order harmonic generation(HHG),which combines nonlinear propagation with macroscopic HHG solving the 3D time-dependent Schrödinger equation at the singleatom level.Our simulations reveal that the nonlinear spatio-temporal reshaping of the drivingfield,observed in the experiment as a bright plasma channel,acts as a self-regulating mechanism boosting the phase-matching conditions for the generation of IAPs.
基金J.B.acknowledges financial support from the European Research Council for ERC Advanced Grant"TRANSFORMER"(788218)ERC Proof of Concept Grant"miniX"(840010),FET-OPEN"PETACom"(829153),FET-OPEN"OPTOlogic"(899794)+5 种基金FET-OPEN"Twisted Nano(101046424),Laserlab-Europe(871124),Marie Sktodowska-Curie ITN"smart-X"(860553)MINECO for Plan Nacional PID2020-112664 GB-I00AGAUR for 2017 SGR 1639,MINECO for"Severo Ochoa"(CEX2019-000910-S)Fundacio Cellex Barcelona,the CERCA Programme/Generalitat de Catalunyathe Alexander von Humboldt Foundation for the Friedrich Wilhelm Bessel Prize.S.S.acknowledges Marie Sktodowska-Curie grant agreement no.713729(COFUND)M.R.and A.M.S.acknowledge Marie Sktodowska-Curie Grant agreement no.754510(PROBIST)。
文摘Unraveling the exact nature of nonequilibrium and correlated interactions is paramount for continued progress in many areas of condensed matter science. Such insight is a prerequisite to develop an engineered approach for smart materials with targeted properties designed to address standing needs such as efficient light harvesting, energy storage, or information processing. For this goal, it is critical to unravel the dynamics of the energy conversion processes between carriers in the earliest time scales of the excitation dynamics. We discuss the implementation and benefits of attosecond soft x-ray core-level spectroscopy up to photon energies of 600 eV for measurements in solid-state systems. In particular, we examine how the pairing between coherent spectral coverage and temporal resolution provides a powerful new insight into the quantum dynamic interactions that determine the macroscopic electronic and optical response. We highlight the different building blocks of the methodology and point out the important aspects for its application from condensed matter studies to materials as thin as 25 nm. Furthermore, we discuss the technological developments in the field of tabletop attosecond soft x-ray sources with time-resolved measurements at the near and extended edge simultaneously and investigate the exciting prospective of extending such technique to the study of 2-dimensional materials.
