Near-Petahertz Fieldoscopy of Liquid

TL;DR

This paper introduces a near-petahertz electric field detection method with ultrahigh temporal resolution, enabling detailed analysis of liquid-phase molecules and expanding capabilities for biological and chemical spectroscopy.

Contribution

The work presents a novel femtosecond fieldoscopy technique that achieves unprecedented detection sensitivity and dynamic range for liquid samples, surpassing existing methods.

Findings

Achieved 200 attosecond temporal resolution in electric field detection.

Demonstrated field-sensitive detection of molecular combination bands in liquids.

Enabled temporal isolation of molecular responses from environmental effects.

Abstract

Measuring transient optical field is pivotal not only for understanding ultrafast phenomena but also for quantitative detection of various molecular species in a sample. In this work, we demonstrate near-petahertz electric field detection of a few femtosecond pulses with 2oo attosecond temporal resolution, 10$^8$ detection dynamic range in electric field and sub-femtojoule detection sensitivity, exceeding those reported by the current methods. By field-resolved detection of the impulsively excited molecules in the liquid phase, termed 'femtosecond fieldoscopy', we demonstrate temporal isolation of the response of the target molecules from those of the environment and the excitation pulse. In a proof-of-concept analysis of aqueous and liquid samples, we demonstrate field-sensitive detection of combination bands of 4.13 {\mu}mol ethanol for the first time. This method expands the scope of aqueous sample analysis to higher detection sensitivity and dynamic range, while the simultaneous direct measurements of phase and intensity information pave the path towards high-resolution biological spectro-microscopy