Ruby Fluorescence System

Absorbed  pump light at 532 nm excites the Cr ion into excited states. The lifetime of  these levels is short 3+ (50 ns), so that the excited ion quickly relaxes by  making a transition to the long-lived metastable state. The energy which is  lost in this process is nonradiative and goes into heating the crystal by  generating phonons or vibrational excitations of the crystal atoms. The  metastable energy level must have a lifetime which is long enough to enable  the Cr ions to remain excited until a photon having the precise energy comes  along to de-excite it.The lasing line in ruby is the so-called  "R1-line" having a wavelength of 694.3 nm. The fluorescence  lifetime of the R1-line is several ms.

Example of ruby fluorescence at high  pressure

With  increasing pressure, this R1 fluorescence shifts to lower energies which  provides us with an accurate estimation of pressure inside the sample c hamber of a DAC.

Capabilities: The Ruby system is mainly used for pressure measurement in DAC.

Contact: Weitao Ding, weitao.ding@hpstar.ac.cn.

Ref: Dewaele A., Torrent M., Loubeyre P. and Mezouar M.,  Phys. Rev. B 78, 104102 (2008); Mao H.K., Xu J., and Bell P.M.  J. Geophys. Res. 91, 4673, (1986).