Multiwall carbon nanotube opto-electronic devices

摘要

A high-sensitivity detector for opto-electronic detection using multiwall carbon nanotubes (MWCNTs) is provided. More specifically, multiwall carbon nanotube films demonstrate an infrared bolometric photoresponse higher than SWCNT films at room temperature. The observed D* exceeding 3.3×106 cm Hz1/2/W with MWCNT-film bolometers and can be further improved to over 1×107 cm Hz1/2/W by adding graphene flakes. The response time of about 1-2 milliseconds with MWCNT bolometers is more than an order of magnitude shorter than that of SWCNT bolometers. For individual MWCNTs with specially designed asymmetric Schottky contacts, one on the sidewall and the other covering the end, the photocurrent has been efficiently harvested and provides a higher detectivity of 6.2×109 cm·Hz1/2/W at room temperature, which is one order of magnitude higher than the convectional VOx detector and makes MWCNT competitive for practical optoelectronic detections over infrared and even longer wavelength range.

主权项

1. An opto-electronic detector for high-sensitivity photo detection, the detector comprising:
a pair of electrodes; at least one multiwall carbon nanotube electrically connecting the pair of electrodes, wherein each of the pair of electrodes are in contact with the at least one multiwall carbon nanotube, and wherein each electrode of the pair of electrodes comprises a Schottky contact on the multiwall carbon nanotube; a current source providing a current to the pair of electrodes; and a voltmeter to detect voltage changes caused by incident photons induced heating of the at least one multiwall carbon nanotube.