Efficient and long-lived Zeeman-sublevel atomic population storage in an erbium-doped glass fiber

TL;DR

This paper reports the first observation of long-lived Zeeman-sublevel population storage in erbium-doped silica glass fiber at cryogenic temperatures, with potential applications in telecommunications.

Contribution

It demonstrates for the first time deep, persistent spectral holes in erbium-doped glass fibers and characterizes their properties, advancing understanding of impurity-vibrational interactions in amorphous hosts.

Findings

Population storage lifetime up to 30 seconds

80% spin polarization achieved

Potential for telecommunication applications

Abstract

Long-lived population storage in optically pumped levels of rare-earth ions doped into solids, referred to as persistent spectral hole burning, is of significant fundamental and technological interest. However, the demonstration of deep and persistent holes in rare-earth ion doped amorphous hosts, e.g. glasses, has remained an open challenge since many decades -- a fact that motivates our work towards a better understanding of the interaction between impurities and vibrational modes in glasses. Here we report the first observation and detailed characterization of such holes in an erbium-doped silica glass fiber cooled to below 1 K. We demonstrate population storage in electronic Zeeman-sublevels of the erbium ground state with lifetimes up to 30 seconds and 80\% spin polarization. In addition to its fundamental aspect, our investigation reveals a potential technological application of rare-earth ion doped amorphous materials, including at telecommunication wavelength.