Molecular Physics

Controlled preparation and vibrational excitation of single ultracold molecular hydrogen ions

Ch. Wellers, M. R. Schenkel, Gouri Shankar Giri, Kenneth R. Brown, Stephan Schiller

Published Nov 17, 2021• 11 citations

Abstract

A single, trapped and ultracold molecular hydrogen ion is an attractive quantum system for exploring various aspects of fundamental physics, such as the determination of fundamental constants and testing their time-independence. Here we demonstrate, for the first time, controlled loading, sympathetic cooling, mass spectrometric identification, and vibrational excitation of ultracold single HD+ ions trapped in a tightly confining radiofrequency trap using single laser-cooled Be+ ions for sympathetic cooling. The apparatus can be used also for preparing other single ions, both lighter and heavier than the coolant ion.

DOI: 10.1080/00268976.2021.2001599

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