Bandlike transport in pentacene and functionalized pentacene thin films revealed by subpicosecond transient photoconductivity measurements

被引:132
作者
Ostroverkhova, O [1 ]
Cooke, DG
Shcherbyna, S
Egerton, RF
Hegmann, FA
Tykwinski, RR
Anthony, JE
机构
[1] Univ Alberta, Dept Phys, Edmonton, AB T6G 2J1, Canada
[2] Univ Alberta, Dept Chem, Edmonton, AB T6G 2G2, Canada
[3] Univ Kentucky, Dept Chem, Lexington, KY 40506 USA
关键词
D O I
10.1103/PhysRevB.71.035204
中图分类号
T [工业技术];
学科分类号
08 ;
摘要
We observe bandlike transport in pentacene and functionalized pentacene thin films using time-resolved terahertz pulse spectroscopy. The measured transient photoconductivity exhibits fast (<400 fs) photogeneration of mobile charge carriers and reveals a transient carrier mobility that increases as the temperature decreases from 300 K down to 10 K, indicative of bandlike transport over subpicosecond time scales. A wavelength-independent photoconductive signal is observed. The transient photoconductivity in the thin-film samples exhibits a single-exponential decay, whereas a power-law decay is seen in single-crystal samples.
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页数:6
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