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arXiv · 2512.04503

Sub-cycle pulse control of holographic and non-holographic electron interferences

Rambabu Rajpoot·Eiji J. Takahashi
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Abstract

We investigate the influence of sub-cycle laser pulses on holographic and non-holographic intracycle interferences by analyzing the photoelectron momentum distributions of helium using TDSE simulations supported by classical trajectory calculations. The results show that the forward-scattering holographic (FSH), backward-scattering holographic (BSH), and time double-slit (TDS) structures are found to be highly sensitive to the pulse duration, carrier-envelope phase (CEP), and temporal envelope in the sub-cycle regime. Sub-cycle pulses with CEP values of $0^\circ$ and $90^\circ$ selectively enhance or suppress distinct features, isolating holographic patterns and enhancing BSH fringes. Classical analysis reveals that the intrinsic chirp inherent to sub-cycle fields shortens the recollision time for scattering trajectories, thereby increasing the fringe spacing in FSH and BSH patterns, while simultaneously enlarging the ATI peak spacing associated with TDS interference. Pulse envelope variations, even at fixed FWHM duration, further reshape the fringe spacings by modifying the instantaneous frequency and vector potential slope near ionization times. These results demonstrate that sub-cycle pulses enable precise temporal control of holographic interference, offering new opportunities for probing and manipulating attosecond electron dynamics.

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Rambabu Rajpoot, Eiji J. Takahashi. 2025-12-04. Sub-cycle pulse control of holographic and non-holographic electron interferences. https://arxiv.org/abs/2512.04503

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