Time-resolved photo-phonon spectroscopy of exchange coupled Cr3+ - pairs in ruby
A. M. Shegeda, V. N. Lisin
Zavoisky Physical- Technical Institute RAS, 420029 Kazan, Russia
PACS: 63.20.-e, 71.55.Ht, 78.40.Ha, 78.47.+p
Abstract
A rather simple method is used to detect at once both
optical absorption spectra and excited-states nonradiative
transitions in 0.03 at.% and 0.16 at.% ruby at temperature
2 K. The technique utilizes a time-resolved bolometer detection
of phonons, generated by the excited-state nonradiative relaxation
following optical excitation with a pulsed tunable dye laser. The
observed excitation spectra of phonons well coincide with already
known absorption spectra of both single chromium ions and pairs of
the nearest neighbors. For the first time the fast (s)resonant energy transfer from single chromium ions to
the fourth-nearest neighbors is observed directly. The new
strongly perturbed Cr-single-ion sites are observed.