Relaxation times of molecular ions OH−in glasses at very low temperature

✍ Scribed by L. Bernard; L. Piche; G. Schumacher; J. Joffrin

• Publisher: Springer US
• Year: 1979
• Tongue: English
• Weight: 862 KB
• Volume: 35
• Category: Article
• ISSN: 0022-2291
• DOI: 10.1007/bf00115589

✦ Synopsis

This paper presents a detailed study of the temperature dependence of the longitudinal relaxation time T I and of the coherence time T e o[ a population of ionic molecular impurities in silica glass. Electric dipolar echoes taken in a temperature range 4-22 mK and a frequency of 370 MHz show that T I is

9 9 -1 9

governed by a one-phonon process; consequently T~ vanes hke T ; expertmental data show that Te also vanes hke T and thts m contradtctton wtth predictions which lead to T -e. The relaxation of the spontaneous and stimulated echoes shows that there is a wide distribution of relaxation times (T I and Te); from the amplitude of the signal it is also possible to extract both the longitudinal and the transverse electric moment; the coupling constant of the impurities with the strain is found to be as large as 3 eV. 411 ~)o22-2291/79/o5oo-o4115o3,oo/o 9 1979 Plenum Publishing Corporation *Suprasil I samples were obtained from Heraeus, France and contain less than 0.5 ppm/weight metallic ions and about 1200 ppm/weight OH-ions.