NMR Studies on3He-3He and3He-4He tunneling motions in solid3He-4He mixtures

✍ Scribed by Yutaka Hirayoshi; Takao Mizusaki; Satoru Maegawa; Akira Hirai

• Publisher: Springer US
• Year: 1978
• Tongue: English
• Weight: 557 KB
• Volume: 30
• Category: Article
• ISSN: 0022-2291
• DOI: 10.1007/bf00115522

✦ Synopsis

Helium-3 nuclear spin relaxation times T1, T2, and Tip have been measured for 3He-4He solid mixtures at the exchange plateau region (~ O. 5 K). The 3He concentrations x3 of the samples were 7.2, 2.9, 1.8, 1.4, 0.67, 0.65, and 0.22 %, and their molar volumes varied between 19.9 and 20.9 cm3 /mole in hcp phase. The spectral density function J(~o) for dipolar field fluctuations was determined in the low-frequency branch from Tip measurements and in the high-frequency branch from conventional T1 measurements. It was (ound that J(to) is given by J(to) = cJ(to)[3.4 + (I -c)J(to)[3_3, where c = (I -x3) 2, j(to)13_ 4 is the spectral density function due to the 3He-4He tunneling motions, and J(o9)[3.3 is that due to the 3He-a He tunneling motions. Using the Torrey theory, the correlation frequency of the 3He-4He tunneling motions was evaluated from Tip data, and was found to be in good agreement with Landesman's theory.