Excitation Dynamics in Disubstituted Polyacetylene
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چکیده
We studied the excitation dynamics in films of disubstituted polyacetylene, a degenerate groundstate conjugated polymer, using psec transient and steady-state spectroscopies. The polymer is found to support charged and neutral topological soliton excitations concurrent with a strong intrinsic photoluminescence band with quantum efficiency, h . 50%. This leads to stimulated emission in thin films and lasing in cylindrical m cavities. The seeming contradiction of a degenerate ground-state polymer with high h is explained by the lowest excited-state ordering. [S0031-9007(99)09122-X]
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تاریخ انتشار 1999