9.6 GHZ AND 34 GHZ ELECTRON PARAMAGNETIC RESONANCE STUDIES OF CHROMIUM-DOPED FORSTERITE
9.6 GHZ AND 34 GHZ ELECTRON PARAMAGNETIC RESONANCE STUDIES OF CHROMIUM-DOPED FORSTERITE
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掺铬镁橄榄石的 9.6 GHz 和 34 GHz 电子顺磁共振研究
DOI：
10.1063/1.467540
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发表时间：
1994
影响因子：
4.4
通讯作者：
J. Freed
中科院分区：
文献类型：
--
作者：
D. Budil;D. Park;J. M. Burlitch;R. Geray;R. Dieckmann;J. Freed
通过电子顺磁共振（EPR）在9.6和34 GHz下检测了在产生高Cr 4 +/Cr 3+比率的条件下生长的掺铬镁橄榄石单晶。晶体通过浮区法在2-3个大气压的氧气中从经由溶胶-凝胶法合成的多晶铬掺杂的镁橄榄石粉末开始生长。研究了铬浓度为110、300和390 ppm的三种晶体。在34 GHz下，观察到在9.6 GHz下不可观察到的激光活性四面体Cr 4+物质的跃迁，这提高了EPR测量磁性参数的分辨率和准确度。此外，非Kramers物质的峰出现在34 GHz处，而在9.6 GHz处未观察到。这些峰没有详细分析，但暂时归因于晶体的八面体取代位点中的Cr 4+。在最高铬浓度下，Cr 3+光谱显示出与Cr 4+直接相互作用的证据。综合的全局最小二乘拟合
Chromium‐doped forsterite single crystals grown under conditions that produce a high Cr4+/Cr3+ ratio were examined by electron paramagnetic resonance (EPR) at 9.6 and 34 GHz. The crystals were grown in 2–3 atm of oxygen by the floating‐zone method starting from polycrystalline chromium‐doped forsterite powder synthesized via a sol–gel method. Three crystals with chromium concentrations of 110, 300, and 390 ppm were studied. At 34 GHz, transitions are observed for the laser‐active tetrahedral Cr4+ species that are not observable at 9.6 GHz, which improve the resolution and accuracy with which the magnetic parameters can be measured by EPR. In addition, peaks for a non‐Kramers species appear at 34 GHz that were not observed at 9.6 GHz. These peaks are not analyzed in detail, but are tentatively ascribed to Cr4+ in the octahedral substitution sites of the crystal. At the highest chromium concentration, the Cr3+ spectra show evidence of direct interaction with Cr4+. A global least‐squares fit of the combined ...