Time modulation of atom sources

TL;DR

This paper analyzes how different aperture functions and pulse schemes affect the temporal modulation and diffraction patterns of atom sources, including revivals and beam profile evolution in matter-wave systems.

Contribution

It systematically discusses the dynamics of atom sources with various aperture functions and pulse schemes, including revival phenomena and beam profile characteristics.

Findings

Aperture functions influence diffraction-in-time oscillations.

Multiple pulses can lead to a saturated, constant beam profile.

Revival phenomena depend on the time scale and pulse overlap.

Abstract

Sudden turn-on of a matter-wave source leads to characteristic oscillations of the probability density which are the hallmark feature of diffraction in time. The apodization of matter waves relies on the use of smooth aperture functions which suppress such oscillations. The analytical dynamics arising with different aperture functions are discussed systematically for switching-on processes, and for single and many-pulse formation procedures. The possibility and time scale of a revival of the diffraction-in-time pattern is also analysed. Similar modulations in time of the pulsed output coupling in atom-lasers are responsible for the dynamical evolution and characteristics of the beam profile. For multiple pulses, different phase schemes and regimes are described and compared. Strongly overlapping pulses lead to a saturated, constant beam profile in time and space, up to the revival phenomenon.