Electron-spin-resonance studies of pristine and heavily doped polyacenic materials.
Electron-spin-resonance studies of pristine and heavily doped polyacenic materials.
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原始和重掺杂多并苯材料的电子自旋共振研究。
DOI：
10.1103/physrevb.35.8368
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发表时间：
1987
期刊：
影响因子：
--
通讯作者：
Yata
中科院分区：
文献类型：
--
作者：
Tanaka;Koike;Yamabe;Yamauchi;Deguchi;Yata
对酚醛树脂热解处理制备的原始和重掺杂多并苯材料进行了电子自旋共振（ESR）研究。选择 500–900 C 范围内的五个热解温度 (T p) 来检查样品的磁性。原始样品的 ESR 线形状和自旋浓度强烈依赖于 T p，反映了每个样品的结构特征。掺杂样品的 ESR 测量以及之前报道的电输运研究得出这样的结论：p 型和 n 型掺杂剂（I 2 和 Na）本质上具有两种作用：（i）清除磁性杂质，其能级存在于费米能级附近；（ii）产生传导载流子，从而提供更宽的 ESR 谱，特别是在较高 T p 下制备的样品中。从这一观察结果来看，在这种掺杂样品中，自旋轨道耦合很可能在弛豫过程中发挥重要作用，这表明导电载流子以有限的概率存在于掺杂剂物质上。
Electron-spin-resonance (ESR) studies of pristine and heavily doped polyacenic materials prepared by pyrolytic treatment of phenolformaldehyde resin have been carried out. Five pyrolysis temperatures (T p) in the range 500–900 C were selected to check the magnetic properties of the samples. The ESR line shapes and the spin concentrations of the pristine samples strongly depend on T p, reflecting the structural characteristics in each sample. The ESR measurement of the doped samples, along with the electrical transport study previously reported, leads to the picture that both the p-type and the n-type dopants (I 2 and Na) essentially have two kinds of roles:(i) scavenging of the magnetic impurities, the energy levels of which exist near the Fermi level, and (ii) generation of conduction carriers giving broadened ESR spectra, particularly in the samples prepared at higher T p. From this observation, it is highly possible that in such doped samples, the spin-orbit coupling plays an important role in the relaxation process, which suggests that the conduction carriers exist on the dopant species with a finite probability.