Field-enhanced photocurrent spectroscopy of excitonic states in single-wall carbon nanotubes.
نویسندگان
چکیده
Excitonic and free-carrier transitions in single-wall carbon nanotubes are distinguished using field-enhanced photocurrent spectroscopy. Electric field dissociation allows for the detection of bound-exciton states that otherwise would not contribute to the photocurrent. Excitonic states associated with both the ground-state semiconductor and the ground-state metallic nanotube transitions are resolved. The observation of a metallic excitonic state corroborates recent predictions of a symmetry gap existing in metallic nanotubes.
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ورودعنوان ژورنال:
- Nano letters
دوره 6 7 شماره
صفحات -
تاریخ انتشار 2006