Fast nuclear spin relaxation in hyperpolarized solid 129Xe.
Fast nuclear spin relaxation in hyperpolarized solid 129Xe.
复制标题
超极化固体 129Xe 中的快速核自旋弛豫。
DOI：
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发表时间：
2002
影响因子：
8.6
通讯作者：
W. Happer
中科院分区：
文献类型：
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作者：
N. Kuzma;B. Patton;K. Raman;W. Happer
本文报道了固体氙中129 π核自旋纵向弛豫时间T_1的新的测量结果。对于温度T <120 K and magnetic fields B>0.05 T，我们发现T1小时的顺序，与以前的测量和预测的声子散射限制的自旋-旋转相互作用，在很好的协议。对于T>120 K，我们的新数据表明，T1可以比声子散射极限短得多。对于B = 0.06 T（常用于积累超极化氙的场），T1在接近氙熔点T（m）= 161.4 K处约为6 s。从T = 50 K到T（m），新的数据与理论预测非常一致，即弛豫是由于（i）声子对自旋-旋转相互作用的调制，以及（ii）空位扩散对偶极-偶极相互作用的调制。
We report extensive new measurements of the longitudinal relaxation time T1 of 129Xe nuclear spins in solid xenon. For temperatures T<120 K and magnetic fields B>0.05 T, we found T1 on the order of hours, in good agreement with previous measurements and with the predicted phonon-scattering limit for the spin-rotation interaction. For T>120 K, our new data show that T1 can be much shorter than the phonon scattering limit. For B = 0.06 T, a field often used to accumulate hyperpolarized xenon, T1 is approximately 6 s near the Xe melting point T(m) = 161.4 K. From T = 50 K to T(m), the new data are in excellent agreement with the theoretical prediction that the relaxation is due to (i) modulation of the spin-rotation interaction by phonons, and (ii) modulation of the dipole-dipole interaction by vacancy diffusion.