Orange avalanche upconversion for high-resolution laser spectroscopy

¹ Laboratoire de Chimie de la Matière Condensée de Paris, CNRS-UMR 7574, École Nationale Supérieure de Chimie de Paris, 11 rue Pierre et Marie Curie, 75005 Paris, France
² Laboratoire Aimé Cotton, CNRS-UPR 3321, Bât. 505, Campus d'Orsay, 91405 Orsay, France

Corresponding author: philippe-goldner@enscp.fr

Received: 26 July 2006
Accepted: 19 October 2006
Published online: 17 January 2007

Abstract

High resolution spectroscopy of quantum systems is a key point in the quantum information field. Rare earth ions in crystals are interesting candidates for this application because of the long coherence lifetime of some of their transitions. These ions can also be manipulated by optical excitation which has, however, to be produced by ultra-stable laser sources. This proves to be a very difficult task in the case of dye lasers which are necessary to excite Pr³⁺ doped crystals and especially Pr³⁺:Y₂SiO₅. This compound is by far the most used host in rare earth based quantum information studies. In this paper, we discuss the use of Pr³⁺,Yb³⁺ codoped materials to build an infrared pumped solid state laser suitable to excite Pr³⁺:Y₂SiO₅ around 606 nm. We show by the analysis of a rate equation model that avalanche upconversion is not very efficient to obtain a high power laser. This is more easily obtained if a second laser is set to pump resonantly Yb³⁺ ions. The spectroscopic properties of a new matrix Pr³⁺,Yb³⁺:PbF₂ are also investigated. We found that this compound emits at 606.18 nm with a width of 5 nm and would be therefore suitable to excite Pr³⁺:Y₂SiO₅. Moreover, it can be excited at 857 nm and 975 nm, i.e. in the range of high power laser diodes.