IEEE Nanophotonics

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Carbon Nanotube Infrared and Terahertz PhotodetectorsFranois Lonard1email: [email protected] Sandia National Laboratories, Livermore, CA, USA

Infrared and terahertz photodetectors are used extensively for applications in defense, communications, medical imaging, component inspection, and thermal imaging. Such detectors are often based on exotic semiconductor materials operated at low temperatures, and new approaches are sought that could lead to uncooled detectors or improved ease of integration with CMOS technology. In this presentation, I will discuss our recent efforts[1-3] at developing and understanding carbon nanotube infrared and terahertz detectors. The detectors are based on macroscopic, optically-thick films of aligned single-wall carbon nanotubes, and are actualized using asymmetric contact electrodes or in p-n junction format. Responsivities of several Volts/Watt are observed in these devices, with a broadband spectral response spanning the visible to the terahertz. A combination of experiment and theory is used to demonstrate the photo-thermoelectric origin of the responsivity and to discuss the performance attributes of such devices.

Figure 1. Images of 3 different types of carbon nanotube photodetectors, and examples of their photoresponse in the infrared and terahertz.[1] S. Nanot, A. W. Cummings, C. L. Pint, A. Ikeuchi, T. Akiho, K. Sueoka, R. H. Hauge, F. Lonard, J. Kono. Sci. Rep. 2013, 3, 1335.[2] X. He, X. Wang, S. Nanot, K. Cong, Q. Jiang, A. A. Kane, J. E. M. Goldsmith, R. H. Hauge, F. Lonard, J. Kono. ACS Nano 2013, 7, 7271.[3] X. He, N. Fujimura, J. M. Lloyd, K. J. Erickson, A. A. Talin, Q. Zhang, W. Gao, Q. Jiang, Y. Kawano, R. H. Hauge, F. Lonard, J. Kono. Nano Lett. 2014, 14, 3953.

Dr. Franois Lonard is Distinguished Member of the Technical Staff in the Materials Physics Department at Sandia National Laboratories in Livermore, CA. His primary research interests are in experimental and theoretical electronics and photonics.Lonard received his Ph.D. in Physics at the University of Toronto, Canada in 1998. He spent two years as a postdoctoral fellow at the IBM T.J. Watson Research Center in Yorktown Heights, NY, before joining Sandia National Laboratories in 2000. Dr. Lonard has authored over 75 journal publications in Nanoscience and Nanotechnology, has given more than 40 invited talks at national and international conferences, and has published a textbook entitled The Physics of Carbon Nanotube Devices.