Alternating-sign photostimulated resonant electrical conductivity of chromium ions in ruby

Nonresonant interaction between phonons with a transition between the components of the 2 E doublet of a chromium ion in ruby

Absorption spectra from excited states of ruby with a high chromium content

Exchange-coupled chromium ion pairs in ruby revisited

Dependence of the width and duration of the luminescence R lines of ruby on the chromium concentration

Magnetic field effect on ion-pair transfer in ruby. Cross relaxations and resonant transfer

Anisotropy of resonant absorption of high-frequency 0.87 X 10 12 Hz phonons in the excited state of Cr 3+ ions in ruby