Dynamic nuclear polarization of high-density atomic hydrogen in solid mixtures of molecular hydrogen isotopes.
Dynamic nuclear polarization of high-density atomic hydrogen in solid mixtures of molecular hydrogen isotopes.
复制标题
分子氢同位素固体混合物中高密度原子氢的动态核极化。
DOI：
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发表时间：
2014
影响因子：
8.6
通讯作者：
D. M. Lee
中科院分区：
文献类型：
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作者：
S. Sheludiakov;J. Ahokas;J. Järvinen;D. Zvezdov;O. Vainio;L. Lehtonen;S. Vasiliev;S. Mao;V. Khmelenko;D. M. Lee
本文报道了在低于1K的温度下，固体氢基质中高密度氢原子和高密度氢原子的磁共振研究。在与D原子交换的化学隧穿反应中，获得了H原子的平均浓度≈为3×10(19) cm(-3)。这些反应的产物是位于D2分子附近的紧密排列的H原子对，具有很强的交换作用。我们发现了通过抽运H电子自旋共振谱中心对H原子产生的动态核极化效应，类似于金属中的Overhauser效应。我们的结果表明，H原子可以以相当于2.6x10(21) cm(-3)的局域浓度的间隔排列在分子基质中。这为在零压下建立原子氢的金属态开辟了一条道路。
We report on magnetic resonance studies of high-density atomic hydrogen and deuterium in solid hydrogen matrices at temperatures below 1 K. Average concentrations of H atoms ≈3×10(19) cm(-3) are obtained in chemical tunneling reactions of isotope exchange with D atoms. The products of these reactions are closely located pairs of H atoms near D2 molecules with strong exchange interactions. We discovered a dynamic nuclear polarization effect on H atoms created by pumping the center of the H electron spin resonance spectrum, similar to the Overhauser effect in metals. Our results indicate that H atoms may be arranged inside molecular matrices at separations equivalent to local concentrations of 2.6×10(21) cm(-3). This opens up a way to build a metallic state of atomic hydrogen at zero pressure.