Modification of radiation pressure due to cooperative scattering of light

TL;DR

This paper investigates how cooperative scattering among atoms alters radiation pressure exerted by a laser, revealing that atom number and collective effects can significantly suppress or enhance the force.

Contribution

It provides an analytical expression for radiation pressure considering cooperative effects, highlighting the impact of atomic distribution and number on the force.

Findings

Radiation pressure depends on collective atomic decay rates.

Directional spontaneous emission can counteract recoil.

Force can be suppressed or enhanced at specific atom numbers.

Abstract

Cooperative spontaneous emission of a single photon from a cloud of N atoms modifies substantially the radiation pressure exerted by a far-detuned laser beam exciting the atoms. On one hand, the force induced by photon absorption depends on the collective decay rate of the excited atomic state. On the other hand, directional spontaneous emission counteracts the recoil induced by the absorption. We derive an analytical expression for the radiation pressure in steady-state. For a smooth extended atomic distribution we show that the radiation pressure depends on the atom number via cooperative scattering and that, for certain atom numbers, it can be suppressed or enhanced.