Hostname: page-component-586b7cd67f-2plfb Total loading time: 0 Render date: 2024-11-28T05:44:29.345Z Has data issue: false hasContentIssue false

Measurement of Ultrafast Carrier Dynamics in Epitaxial Graphene

Published online by Cambridge University Press:  01 February 2011

Jahan M. Dawlaty
Affiliation:
[email protected], Cornell University, ECE, 113 Philips Hall, Cornell University, Ithaca, NY, 14853, United States, 607-255-5868
Shriram Shivaraman
Affiliation:
[email protected], Cornell University, Electrical and Computer Engineering, Philips Hall, Cornell University, Ithaca, NY, 14853, United States
Mvs Chandrashekhar
Affiliation:
[email protected], Cornell University, Electrical and Computer Engineering, Philips Hall, Cornell University, Ithaca, NY, 14853, United States
Michael G. Spencer
Affiliation:
[email protected], Cornell University, Electrical and Computer Engineering, Philips Hall, Cornell University, Ithaca, NY, 14853, United States
Farhan Rana
Affiliation:
[email protected], Cornell University, Electrical and Computer Engineering, Philips Hall, Cornell University, Ithaca, NY, 14853, United States
Get access

Abstract

Using ultrafast optical pump-probe spectroscopy, we have measured carrier relaxation times in epitaxial graphene layers grown on SiC wafers. We find two distinct time scales associated with the relaxation of nonequilibrium photogenerated carriers. An initial fast relaxation transient in the 70-120 fs range is followed by a slower relaxation process in the 0.4-1.7 ps range. The slower relaxation time is found to be inversely proportional to the degree of crystalline disorder in the graphene layers as measured by Raman spectroscopy. We relate the measured fast and slow time constants to carrier-carrier and carrier-phonon intraband and interband scattering processes in graphene.

Type
Research Article
Copyright
Copyright © Materials Research Society 2008

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

1. Saito, R., Dresselhaus, G., Dresselhaus, M. S., Physical Properties of Carbon Nanotubes, Imperial College Press, London, UK (1999).Google Scholar
2. Novoselov, K. S., Geim, A. K., Morozov, S. V., Jiang, D., Katsnelson, M. I., Grigorieva, I. V., Dubonos, S. V., Firsov, A. A., Nature, 438, 197 (2005).Google Scholar
3. Zhang, Y., Tan, Y., Stormer, H. L., Kim, P., Nature, 438, 201 (2005).Google Scholar
4. Berger, C., Song, Z., Li, X., Wu, X., Brown, N., Naud, C., Mayou, D., Li, T., Hass, J., Marchenkov, A. N., Conrad, E. H., First, P. N., W. A. de Heer, Science, 312, 1191 (2006).Google Scholar
5. Liang, G., Neophytou, N., Nikonov, D. E., Lundstrom, M. S., IEEE Trans. Elec. Dev., 54, 657 (2007).Google Scholar
6. Williams, J. R., DiCarlo, L., Marcus, C. M., Science, 317, 638 (2007).Google Scholar
7. Gu, G., Nie, S., Feenstra, R. M., Devaty, R. P., Choyke, W. J., Chan, W. K., Kane, M. G., Appl. Phys. Lett., 90, 253507 (2007).Google Scholar
8. Rana, F., IEEE Trans. Nanotechnol. 7, 91 (2008).Google Scholar
9. Ohta, T., Bostwick, A., Seyller, T., Horn, K., Rotenberg, E., Sicence, 313, 951 (2006).Google Scholar
10. Ma, Y., Stenger, J., Zimmermann, J., Bachilo, S. M., Smalley, R. E., Weisman, R. B., Fleming, G. R., J. Chem. Phys. 120, 3368 (2004).Google Scholar
11. Seibert, K., Cho, G.C., Kütt, W., Kurz, H., Reitze, D.H., Dadap, J.I., Ahn, H., Downer, M.C., Malvezzi, A.M., Phys. Rev. B. 42, 2842 (1990).Google Scholar
12. Ferrari, A. C., Meyer, J. C., Scardaci, V., Casiraghi, C., Lazzeri, M., Mauri, F., Piscanec, S., Jiang, D., Novoselov, K. S., Roth, S., Geim, A. K., Phys. Rev. Letts., 97, 187401 (2006).Google Scholar
13. Faugeras, C., Nerriere, A., Potemski, M., Mahmood, A., Dujardin, E., Berger, C., Heer, W. A. de, cond-mat 0709 2538 (2007).Google Scholar
14. Dawlaty, J., Shivaraman, S., Strait, J., George, P., Chandrashekhar, M., Rana, F., Spencer, M. G., Veksler, D., Chen, Y., submitted to Phys. Rev. Lett., also appears at arXiv:0801.3302 (2008).Google Scholar
15. Cumpson, P. J, Surface and Interface Analysis, 29, 403 (2000).Google Scholar
16. Hwang, E. H., Hu, B. Y., Sarma, S. Das, Phys. Revs. B, 76, 115434 (2007).Google Scholar
17. Rana, F., Phys. Rev. B, {\bf 76}, 155431 (2007).Google Scholar
18. Sergeev, A., M. Yu. Reizer, Mitin, V., Phys. Rev. Letts., 94, 136602 (2005).Google Scholar
19. Ferrari, A. C., Robertson, J., Phys. Rev. B, 61, 14095 (2000).Google Scholar
20. Kartner, F. X., Au, J. A. der, Keller, U., IEEE J. Sel. Top. Quantum Electron., 4, 159 (1998).Google Scholar
21. Zhou, S.Y., Gweon, G. H., Fedorov, A. V., First, P. N., Heer, W. A. de, Lee, D. H., Guinea, F., Neto, A. H. Castro, Lanzara, A., Nature Materials, 6, 770 (2007).Google Scholar