This work demonstrates the generation and characterization of isolated sub-100-attosecond pulses of extreme ultraviolet (XUV) light through the use of single-cycle nonlinear optics. By using waveform-controlled sub-1.5-cycle near-infrared (NIR) light, the researchers achieved robust, energetic, isolated XUV pulses with high conversion efficiency (~10^-6). These pulses enable the study of electron motion and electron-electron interactions with atomic-scale resolution (~24 as). The key finding is that ionization is confined to a single wave cycle of the NIR field, allowing for precise temporal control and enabling the observation of sub-cycle ionization events and electron trajectories. The XUV pulses are generated through the interaction of the NIR field with neon atoms, resulting in high-harmonic photons and electrons emitted by above-threshold ionization. The XUV pulses are then characterized using time-resolved measurements and the atomic transient recorder (ATR) technique. The results show excellent agreement between the measured and simulated data, confirming the reliability of the retrieved XUV pulse parameters. The study also highlights the importance of controlling the carrier-envelope phase to achieve high contrast and efficient XUV generation. The results have implications for the development of attosecond spectroscopy and the study of electron dynamics in atoms and molecules. The work provides a foundation for future studies of strong-field ionization and electron-electron interactions with high temporal resolution.This work demonstrates the generation and characterization of isolated sub-100-attosecond pulses of extreme ultraviolet (XUV) light through the use of single-cycle nonlinear optics. By using waveform-controlled sub-1.5-cycle near-infrared (NIR) light, the researchers achieved robust, energetic, isolated XUV pulses with high conversion efficiency (~10^-6). These pulses enable the study of electron motion and electron-electron interactions with atomic-scale resolution (~24 as). The key finding is that ionization is confined to a single wave cycle of the NIR field, allowing for precise temporal control and enabling the observation of sub-cycle ionization events and electron trajectories. The XUV pulses are generated through the interaction of the NIR field with neon atoms, resulting in high-harmonic photons and electrons emitted by above-threshold ionization. The XUV pulses are then characterized using time-resolved measurements and the atomic transient recorder (ATR) technique. The results show excellent agreement between the measured and simulated data, confirming the reliability of the retrieved XUV pulse parameters. The study also highlights the importance of controlling the carrier-envelope phase to achieve high contrast and efficient XUV generation. The results have implications for the development of attosecond spectroscopy and the study of electron dynamics in atoms and molecules. The work provides a foundation for future studies of strong-field ionization and electron-electron interactions with high temporal resolution.