Ultrafast dynamics observed at low energies carry insightful information about the complex many-body interactions in solid-state materials.Here,we present a highly sensitive and robust setup for asymmetric 2-dimension...Ultrafast dynamics observed at low energies carry insightful information about the complex many-body interactions in solid-state materials.Here,we present a highly sensitive and robust setup for asymmetric 2-dimensional spectroscopy performing 2-pulse visible excitation combined with probing in the 15-to 35-THz frequency range.This experimental setup is ideal for targeting the interplay of high-and low-energy correlations in functional materials with femtosecond temporal and millielectronvolt energy resolution.In addition,the sub-cycle field resolution of mid-infrared pulses enables tracking nonthermal interactions in the complex dielectric function.Prototypical measurements benchmark ultrafast carrier dynamics in thin-film graphite,showing in detail the interplay of direct and indirect optical transitions in the transient excited state.We further investigate the photo-induced collapse of the superconducting condensate in the high-temperature superconductor Bi_(2)Sr_(2)CaCu_(2)O_(8+x)at energies resonant to the optical bandgap,revealing a nontrivial instantaneous nonlinearity related to the excited quasiparticles in the material.Optical pump–terahertz probe experiments build the foundation for this evolutionary step in 2-dimensional spectroscopy as well as for terahertz 4-wave mixing with resonant driving and readout of the superconducting state.Our results offer exciting perspectives in the study of strong correlations and enable precise investigations of nontrivial many-body interactions in few-layer samples and nanostructures.展开更多
基金supported by the FEDER Program(Grant No.2017-03-022-19“Lux-Ultra-Fast”and Grant No.2023-01-04“Lux-Ultra-Fast 2”).
文摘Ultrafast dynamics observed at low energies carry insightful information about the complex many-body interactions in solid-state materials.Here,we present a highly sensitive and robust setup for asymmetric 2-dimensional spectroscopy performing 2-pulse visible excitation combined with probing in the 15-to 35-THz frequency range.This experimental setup is ideal for targeting the interplay of high-and low-energy correlations in functional materials with femtosecond temporal and millielectronvolt energy resolution.In addition,the sub-cycle field resolution of mid-infrared pulses enables tracking nonthermal interactions in the complex dielectric function.Prototypical measurements benchmark ultrafast carrier dynamics in thin-film graphite,showing in detail the interplay of direct and indirect optical transitions in the transient excited state.We further investigate the photo-induced collapse of the superconducting condensate in the high-temperature superconductor Bi_(2)Sr_(2)CaCu_(2)O_(8+x)at energies resonant to the optical bandgap,revealing a nontrivial instantaneous nonlinearity related to the excited quasiparticles in the material.Optical pump–terahertz probe experiments build the foundation for this evolutionary step in 2-dimensional spectroscopy as well as for terahertz 4-wave mixing with resonant driving and readout of the superconducting state.Our results offer exciting perspectives in the study of strong correlations and enable precise investigations of nontrivial many-body interactions in few-layer samples and nanostructures.
