Attosecond spectroscopy of liquid water

Abstract

Electronic dynamics in liquids are of fundamental importance, but time-resolved experiments have so far remained limited to the femtosecond time scale. We report the extension of attosecond spectroscopy to the liquid phase. We measured time delays of 50 to 70 attoseconds between the photoemission from liquid water and that from gaseous water at photon energies of 21.7 to 31.0 electron volts. These photoemission delays can be decomposed into a photoionization delay sensitive to the local environment and a delay originating from electron transport. In our experiments, the latter contribution is shown to be negligible. By referencing liquid water to gaseous water, we isolated the effect of solvation on the attosecond photoionization dynamics of water molecules. Our methods define an approach to separating bound and unbound electron dynamics from the structural response of the solvent.

Revealing the Target Electronic Structure with Under-Threshold RABBITT

“…However, Figure 3b displays very clearly that the subsequent ionization process nl + ω → E(l ± 1) favors very strongly the nd intermediate states and the ns states can be safely ignored in uRABBITT. We see from the same Figure 3b that the photoionization cross-sections σ nd depend rather weakly on n, and it is the oscillator strength factor f 1/2 nd that determines largely the resonant amplitude (6) in Ne.…”

“…We use the software package ATOM [23] to peform the calculations of the quantities E nl , f nl , and σ nl entering Equation (6). These results are presented in Table 1 and displayed graphically in Figure 3.…”

“…The process of reconstruction of attosecond beating by the interference of two-photon transitions (RABBITT) [1,2] has become a widely used tool for attosecond chronoscopy of atoms [3], molecules [4,5] liquids [6], and solids [7,8]. In RABBITT, XUV driven primary ionization is augmented by secondary IR photon absorption or emission.…”

Symmetry resolved atomic photoionization phase shift by attosecond coincidence metrology

“…Both techniques have been applied to a wide range of attosecond time-resolved photoelectron emission dynamics in atoms [6][7][8] , molecules [9][10][11] and even condensed matters [12][13][14][15] . Studies have demonstrated the photoelectron emission time delays arising from different ionization shells [16][17][18] , shape resonances 9,10,19 , electron correlation 20 , orbital asymmetry 21 , spatial asymmetry (chirality) 11 , and electron delocalization 22 .…”

Sub-7-femtosecond conical-intersection dynamics probed at the carbon K-edge

“…But how fast electronic relaxation really is has remained elusive in many molecular systems, owing to experimental limitations, particularly temporal resolution. This situation has changed with the advent of attosecond science that has redefined the frontiers of time-resolved measurements on molecules (7)(8)(9)(10)(11)(12)(13)(14). Attosecond transient-absorption spectroscopy (ATAS) is a particularly powerful technique for accessing both electronic and structural dynamics (15)(16)(17)(18)(19)(20)(21).…”