Abstract

Reduced graphene oxides with varying degrees of reduction have been produced by hydrazine reduction of graphene oxide. The linear and nonlinear optical properties of both graphene oxide as well as the reduced graphene oxides have been measured by single beam Z-scan measurement in the picosecond region. The results reveal both saturable absorption and two-photon absorption, strongly dependent on the intensity of the pump pulse: saturable absorption occurs at lower pump pulse intensity (~1.5 GW/cm2 saturation intensity) whereas two-photon absorption dominates at higher intensities (≥5.7 GW/cm2). Intriguingly, we find that the two-photon absorption coefficient (from 1.5 cm/GW to 4.5cm/GW) and the saturation intensity (from 1 GW/cm2 to 2 GW/cm2) vary with chemical reduction, which is ascribed to the varying concentrations of sp2 domains and sp2 clusters in the reduced graphene oxides. Our results not only provide an insight into the evolution of the nonlinear optical coefficient in reduced graphene oxide, but also suggest that chemical engineering techniques may usefully be applied to tune the nonlinear optical properties of various nano-materials, including atomically thick graphene sheets.

© 2014 Optical Society of America

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2014 (1)

2013 (3)

X. L. Zhang, Z. B. Liu, X. C. Li, Q. Ma, X. D. Chen, J. G. Tian, Y. F. Xu, and Y. S. Chen, “Transient thermal effect, nonlinear refraction and nonlinear absorption properties of graphene oxide sheets in dispersion,” Opt. Express 21(6), 7511–7520 (2013).
[CrossRef] [PubMed]

T. Remyamol, H. John, and P. Gopinath, “Synthesis and nonlinear optical properties of reduced graphene oxide covalently functionalized with polyaniline,” Carbon 59, 308–314 (2013).
[CrossRef]

A. Martinez and Z. P. Sun, “Nanotube and graphene saturable absorbers for fibre lasers,” Nat. Photonics 7(11), 842–845 (2013).
[CrossRef]

2012 (7)

Z. Sun, T. Hasan, and A. C. Ferrari, “Ultrafast lasers mode-locked by nanotubes and graphene,” Physica E 44(6), 1082–1091 (2012).
[CrossRef]

A. Y. Bykov, T. V. Murzina, M. G. Rybin, and E. D. Obraztsova, “Second harmonic generation in multilayer graphene induced by direct electric current,” Phys. Rev. B 85(12), 121413 (2012).
[CrossRef]

H. Zhang, S. Virally, Q. L. Bao, L. K. Ping, S. Massar, N. Godbout, and P. Kockaert, “Z-scan measurement of the nonlinear refractive index of graphene,” Opt. Lett. 37(11), 1856–1858 (2012).
[CrossRef] [PubMed]

X. F. Jiang, L. Polavarapu, S. T. Neo, T. Venkatesan, and Q. H. Xu, “Graphene oxides as tunable broadband nonlinear optical materials for femtosecond laser pulses,” J. Phys. Chem. Lett. 3(6), 785–790 (2012).
[CrossRef]

F. Bonaccorso, A. Lombardo, T. Hasan, Z. P. Sun, L. Colombo, and A. C. Ferrari, “Production and processing of graphene and 2d crystals,” Mater. Today 15(12), 564–589 (2012).
[CrossRef]

L. Z. Liu, L. Wang, J. F. Gao, J. J. Zhao, X. F. Gao, and Z. F. Chen, “Amorphous structural models for graphene oxides,” Carbon 50(4), 1690–1698 (2012).
[CrossRef]

S. F. Pei and H. M. Cheng, “The reduction of graphene oxide,” Carbon 50(9), 3210–3228 (2012).
[CrossRef]

2011 (4)

X. L. Zhang, X. Zhao, Z. B. Liu, S. Shi, W. Y. Zhou, J. G. Tian, Y. F. Xu, and Y. S. Chen, “Nonlinear optical and optical limiting properties of graphene oxide-fe3o4 hybrid material,” J. Opt. 13(7), 075202 (2011).
[CrossRef]

Z.-B. Liu, X. Zhao, X.-L. Zhang, X.-Q. Yan, Y.-P. Wu, Y.-S. Chen, and J.-G. Tian, “Ultrafast dynamics and nonlinear optical responses from sp2- and sp3-hybridized domains in graphene oxide,” J. Phys. Chem. Lett. 2(16), 1972–1977 (2011).
[CrossRef]

Y. Shen, P. Zhou, Q. Q. Sun, L. Wan, J. Li, L. Y. Chen, D. W. Zhang, and X. B. Wang, “Optical investigation of reduced graphene oxide by spectroscopic ellipsometry and the band-gap tuning,” Appl. Phys. Lett. 99(14), 141911 (2011).
[CrossRef]

S. Saxena, T. A. Tyson, S. Shukla, E. Negusse, H. Y. Chen, and J. M. Bai, “Investigation of structural and electronic properties of graphene oxide,” Appl. Phys. Lett. 99(1), 013104 (2011).
[CrossRef]

2010 (9)

V. H. Pham, T. V. Cuong, T. D. Nguyen-Phan, H. D. Pham, E. J. Kim, S. H. Hur, E. W. Shin, S. Kim, and J. S. Chung, “One-step synthesis of superior dispersion of chemically converted graphene in organic solvents,” Chem. Commun. (Camb.) 46(24), 4375–4377 (2010).
[CrossRef] [PubMed]

J. J. Dean and H. M. van Driel, “Graphene and few-layer graphite probed by second-harmonic generation: Theory and experiment,” Phys. Rev. B 82(12), 125411 (2010).
[CrossRef]

E. Hendry, P. J. Hale, J. Moger, A. K. Savchenko, and S. A. Mikhailov, “Coherent nonlinear optical response of graphene,” Phys. Rev. Lett. 105(9), 097401 (2010).
[CrossRef] [PubMed]

Z. P. Sun, T. Hasan, F. Torrisi, D. Popa, G. Privitera, F. Q. Wang, F. Bonaccorso, D. M. Basko, and A. C. Ferrari, “Graphene mode-locked ultrafast laser,” ACS Nano 4(2), 803–810 (2010).
[CrossRef] [PubMed]

Z. P. Sun, D. Popa, T. Hasan, F. Torrisi, F. Q. Wang, E. J. R. Kelleher, J. C. Travers, V. Nicolosi, and A. C. Ferrari, “A stable, wideband tunable, near transform-limited, graphene-mode-locked, ultrafast laser,” Nano Res. 3(9), 653–660 (2010).
[CrossRef]

F. Bonaccorso, Z. Sun, T. Hasan, and A. C. Ferrari, “Graphene photonics and optoelectronics,” Nat. Photonics 4(9), 611–622 (2010).
[CrossRef]

K. P. Loh, Q. Bao, G. Eda, and M. Chhowalla, “Graphene oxide as a chemically tunable platform for optical applications,” Nat. Chem. 2(12), 1015–1024 (2010).
[CrossRef] [PubMed]

G. Eda, Y. Y. Lin, C. Mattevi, H. Yamaguchi, H. A. Chen, I. S. Chen, C. W. Chen, and M. Chhowalla, “Blue photoluminescence from chemically derived graphene oxide,” Adv. Mater. 22(4), 505–509 (2010).
[CrossRef] [PubMed]

H. X. Chang, Z. H. Sun, Q. H. Yuan, F. Ding, X. M. Tao, F. Yan, and Z. J. Zheng, “Thin film field-effect phototransistors from bandgap-tunable, solution-processed, few-layer reduced graphene oxide films,” Adv. Mater. 22(43), 4872–4876 (2010).
[CrossRef] [PubMed]

2009 (5)

Y. B. Zhang, T. T. Tang, C. Girit, Z. Hao, M. C. Martin, A. Zettl, M. F. Crommie, Y. R. Shen, and F. Wang, “Direct observation of a widely tunable bandgap in bilayer graphene,” Nature 459(7248), 820–823 (2009).
[CrossRef] [PubMed]

Z. B. Liu, Y. Wang, X. L. Zhang, Y. F. Xu, Y. S. Chen, and J. G. Tian, “Nonlinear optical properties of graphene oxide in nanosecond and picosecond regimes,” Appl. Phys. Lett. 94(2), 021902 (2009).
[CrossRef]

S. Park, J. H. An, I. W. Jung, R. D. Piner, S. J. An, X. S. Li, A. Velamakanni, and R. S. Ruoff, “Colloidal suspensions of highly reduced graphene oxide in a wide variety of organic solvents,” Nano Lett. 9(4), 1593–1597 (2009).
[CrossRef] [PubMed]

T. Hasan, Z. P. Sun, F. Q. Wang, F. Bonaccorso, P. H. Tan, A. G. Rozhin, and A. C. Ferrari, “Nanotube-polymer composites for ultrafast photonics,” Adv. Mater. 21(38–39), 3874–3899 (2009).
[CrossRef]

M. Breusing, C. Ropers, and T. Elsaesser, “Ultrafast carrier dynamics in graphite,” Phys. Rev. Lett. 102(8), 086809 (2009).
[CrossRef] [PubMed]

2008 (2)

R. R. Nair, P. Blake, A. N. Grigorenko, K. S. Novoselov, T. J. Booth, T. Stauber, N. M. R. Peres, and A. K. Geim, “Fine structure constant defines visual transparency of graphene,” Science 320(5881), 1308 (2008).
[CrossRef] [PubMed]

K. F. Mak, M. Y. Sfeir, Y. Wu, C. H. Lui, J. A. Misewich, and T. F. Heinz, “Measurement of the optical conductivity of graphene,” Phys. Rev. Lett. 101(19), 196405 (2008).
[CrossRef] [PubMed]

2007 (2)

C. Gómez-Navarro, R. T. Weitz, A. M. Bittner, M. Scolari, A. Mews, M. Burghard, and K. Kern, “Electronic transport properties of individual chemically reduced graphene oxide sheets,” Nano Lett. 7(11), 3499–3503 (2007).
[CrossRef] [PubMed]

S. Y. Zhou, G. H. Gweon, A. V. Fedorov, P. N. First, W. A. de Heer, D. H. Lee, F. Guinea, A. H. Castro Neto, and A. Lanzara, “Substrate-induced bandgap opening in epitaxial graphene,” Nat. Mater. 6(10), 770–775 (2007).
[CrossRef] [PubMed]

2000 (2)

A. C. Ferrari and J. Robertson, “Interpretation of raman spectra of disordered and amorphous carbon,” Phys. Rev. B 61(20), 14095–14107 (2000).
[CrossRef]

S. Yumitori, “Correlation of c1s chemical state intensities with the o1s intensity in the xps analysis of anodically oxidized glass-like carbon samples,” J. Mater. Sci. 35(1), 139–146 (2000).
[CrossRef]

1999 (1)

1993 (1)

R. J. Waltman, J. Pacansky, and C. W. Bates, “X-ray photoelectron spectroscopic studies on organic photoconductors evaluation of atomic charges on chlorodiane blue and p(diethylamino)benzaldehyde diphenylhydrazone,” Chem. Mater. 5(12), 1799–1804 (1993).
[CrossRef]

1990 (1)

M. Sheikbahae, A. A. Said, T. H. Wei, D. J. Hagan, and E. W. Vanstryland, “Sensitive measurement of optical nonlinearities using a single beam,” IEEE J. Quantum Electron. 26(4), 760–769 (1990).
[CrossRef]

1987 (1)

J. Robertson and E. P. O’Reilly, “Electronic and atomic structure of amorphous carbon,” Phys. Rev. B Condens. Matter 35(6), 2946–2957 (1987).
[CrossRef] [PubMed]

An, J. H.

S. Park, J. H. An, I. W. Jung, R. D. Piner, S. J. An, X. S. Li, A. Velamakanni, and R. S. Ruoff, “Colloidal suspensions of highly reduced graphene oxide in a wide variety of organic solvents,” Nano Lett. 9(4), 1593–1597 (2009).
[CrossRef] [PubMed]

An, S. J.

S. Park, J. H. An, I. W. Jung, R. D. Piner, S. J. An, X. S. Li, A. Velamakanni, and R. S. Ruoff, “Colloidal suspensions of highly reduced graphene oxide in a wide variety of organic solvents,” Nano Lett. 9(4), 1593–1597 (2009).
[CrossRef] [PubMed]

Bai, J. M.

S. Saxena, T. A. Tyson, S. Shukla, E. Negusse, H. Y. Chen, and J. M. Bai, “Investigation of structural and electronic properties of graphene oxide,” Appl. Phys. Lett. 99(1), 013104 (2011).
[CrossRef]

Bao, Q.

K. P. Loh, Q. Bao, G. Eda, and M. Chhowalla, “Graphene oxide as a chemically tunable platform for optical applications,” Nat. Chem. 2(12), 1015–1024 (2010).
[CrossRef] [PubMed]

Bao, Q. L.

Basko, D. M.

Z. P. Sun, T. Hasan, F. Torrisi, D. Popa, G. Privitera, F. Q. Wang, F. Bonaccorso, D. M. Basko, and A. C. Ferrari, “Graphene mode-locked ultrafast laser,” ACS Nano 4(2), 803–810 (2010).
[CrossRef] [PubMed]

Bates, C. W.

R. J. Waltman, J. Pacansky, and C. W. Bates, “X-ray photoelectron spectroscopic studies on organic photoconductors evaluation of atomic charges on chlorodiane blue and p(diethylamino)benzaldehyde diphenylhydrazone,” Chem. Mater. 5(12), 1799–1804 (1993).
[CrossRef]

Bittner, A. M.

C. Gómez-Navarro, R. T. Weitz, A. M. Bittner, M. Scolari, A. Mews, M. Burghard, and K. Kern, “Electronic transport properties of individual chemically reduced graphene oxide sheets,” Nano Lett. 7(11), 3499–3503 (2007).
[CrossRef] [PubMed]

Blake, P.

R. R. Nair, P. Blake, A. N. Grigorenko, K. S. Novoselov, T. J. Booth, T. Stauber, N. M. R. Peres, and A. K. Geim, “Fine structure constant defines visual transparency of graphene,” Science 320(5881), 1308 (2008).
[CrossRef] [PubMed]

Bonaccorso, F.

F. Bonaccorso and Z. P. Sun, “Solution processing of graphene, topological insulators and other 2d crystals for ultrafast photonics,” Opt. Mater. Express 4(1), 63–78 (2014).
[CrossRef]

F. Bonaccorso, A. Lombardo, T. Hasan, Z. P. Sun, L. Colombo, and A. C. Ferrari, “Production and processing of graphene and 2d crystals,” Mater. Today 15(12), 564–589 (2012).
[CrossRef]

F. Bonaccorso, Z. Sun, T. Hasan, and A. C. Ferrari, “Graphene photonics and optoelectronics,” Nat. Photonics 4(9), 611–622 (2010).
[CrossRef]

Z. P. Sun, T. Hasan, F. Torrisi, D. Popa, G. Privitera, F. Q. Wang, F. Bonaccorso, D. M. Basko, and A. C. Ferrari, “Graphene mode-locked ultrafast laser,” ACS Nano 4(2), 803–810 (2010).
[CrossRef] [PubMed]

T. Hasan, Z. P. Sun, F. Q. Wang, F. Bonaccorso, P. H. Tan, A. G. Rozhin, and A. C. Ferrari, “Nanotube-polymer composites for ultrafast photonics,” Adv. Mater. 21(38–39), 3874–3899 (2009).
[CrossRef]

Booth, T. J.

R. R. Nair, P. Blake, A. N. Grigorenko, K. S. Novoselov, T. J. Booth, T. Stauber, N. M. R. Peres, and A. K. Geim, “Fine structure constant defines visual transparency of graphene,” Science 320(5881), 1308 (2008).
[CrossRef] [PubMed]

Breusing, M.

M. Breusing, C. Ropers, and T. Elsaesser, “Ultrafast carrier dynamics in graphite,” Phys. Rev. Lett. 102(8), 086809 (2009).
[CrossRef] [PubMed]

Burghard, M.

C. Gómez-Navarro, R. T. Weitz, A. M. Bittner, M. Scolari, A. Mews, M. Burghard, and K. Kern, “Electronic transport properties of individual chemically reduced graphene oxide sheets,” Nano Lett. 7(11), 3499–3503 (2007).
[CrossRef] [PubMed]

Bykov, A. Y.

A. Y. Bykov, T. V. Murzina, M. G. Rybin, and E. D. Obraztsova, “Second harmonic generation in multilayer graphene induced by direct electric current,” Phys. Rev. B 85(12), 121413 (2012).
[CrossRef]

Castro Neto, A. H.

S. Y. Zhou, G. H. Gweon, A. V. Fedorov, P. N. First, W. A. de Heer, D. H. Lee, F. Guinea, A. H. Castro Neto, and A. Lanzara, “Substrate-induced bandgap opening in epitaxial graphene,” Nat. Mater. 6(10), 770–775 (2007).
[CrossRef] [PubMed]

Chang, H. X.

H. X. Chang, Z. H. Sun, Q. H. Yuan, F. Ding, X. M. Tao, F. Yan, and Z. J. Zheng, “Thin film field-effect phototransistors from bandgap-tunable, solution-processed, few-layer reduced graphene oxide films,” Adv. Mater. 22(43), 4872–4876 (2010).
[CrossRef] [PubMed]

Chen, C. W.

G. Eda, Y. Y. Lin, C. Mattevi, H. Yamaguchi, H. A. Chen, I. S. Chen, C. W. Chen, and M. Chhowalla, “Blue photoluminescence from chemically derived graphene oxide,” Adv. Mater. 22(4), 505–509 (2010).
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Chen, H. A.

G. Eda, Y. Y. Lin, C. Mattevi, H. Yamaguchi, H. A. Chen, I. S. Chen, C. W. Chen, and M. Chhowalla, “Blue photoluminescence from chemically derived graphene oxide,” Adv. Mater. 22(4), 505–509 (2010).
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Chen, H. Y.

S. Saxena, T. A. Tyson, S. Shukla, E. Negusse, H. Y. Chen, and J. M. Bai, “Investigation of structural and electronic properties of graphene oxide,” Appl. Phys. Lett. 99(1), 013104 (2011).
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G. Eda, Y. Y. Lin, C. Mattevi, H. Yamaguchi, H. A. Chen, I. S. Chen, C. W. Chen, and M. Chhowalla, “Blue photoluminescence from chemically derived graphene oxide,” Adv. Mater. 22(4), 505–509 (2010).
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Chen, L. Y.

Y. Shen, P. Zhou, Q. Q. Sun, L. Wan, J. Li, L. Y. Chen, D. W. Zhang, and X. B. Wang, “Optical investigation of reduced graphene oxide by spectroscopic ellipsometry and the band-gap tuning,” Appl. Phys. Lett. 99(14), 141911 (2011).
[CrossRef]

Chen, X. D.

Chen, Y. S.

X. L. Zhang, Z. B. Liu, X. C. Li, Q. Ma, X. D. Chen, J. G. Tian, Y. F. Xu, and Y. S. Chen, “Transient thermal effect, nonlinear refraction and nonlinear absorption properties of graphene oxide sheets in dispersion,” Opt. Express 21(6), 7511–7520 (2013).
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X. L. Zhang, X. Zhao, Z. B. Liu, S. Shi, W. Y. Zhou, J. G. Tian, Y. F. Xu, and Y. S. Chen, “Nonlinear optical and optical limiting properties of graphene oxide-fe3o4 hybrid material,” J. Opt. 13(7), 075202 (2011).
[CrossRef]

Z. B. Liu, Y. Wang, X. L. Zhang, Y. F. Xu, Y. S. Chen, and J. G. Tian, “Nonlinear optical properties of graphene oxide in nanosecond and picosecond regimes,” Appl. Phys. Lett. 94(2), 021902 (2009).
[CrossRef]

Chen, Y.-S.

Z.-B. Liu, X. Zhao, X.-L. Zhang, X.-Q. Yan, Y.-P. Wu, Y.-S. Chen, and J.-G. Tian, “Ultrafast dynamics and nonlinear optical responses from sp2- and sp3-hybridized domains in graphene oxide,” J. Phys. Chem. Lett. 2(16), 1972–1977 (2011).
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Chen, Z. F.

L. Z. Liu, L. Wang, J. F. Gao, J. J. Zhao, X. F. Gao, and Z. F. Chen, “Amorphous structural models for graphene oxides,” Carbon 50(4), 1690–1698 (2012).
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S. F. Pei and H. M. Cheng, “The reduction of graphene oxide,” Carbon 50(9), 3210–3228 (2012).
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K. P. Loh, Q. Bao, G. Eda, and M. Chhowalla, “Graphene oxide as a chemically tunable platform for optical applications,” Nat. Chem. 2(12), 1015–1024 (2010).
[CrossRef] [PubMed]

G. Eda, Y. Y. Lin, C. Mattevi, H. Yamaguchi, H. A. Chen, I. S. Chen, C. W. Chen, and M. Chhowalla, “Blue photoluminescence from chemically derived graphene oxide,” Adv. Mater. 22(4), 505–509 (2010).
[CrossRef] [PubMed]

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V. H. Pham, T. V. Cuong, T. D. Nguyen-Phan, H. D. Pham, E. J. Kim, S. H. Hur, E. W. Shin, S. Kim, and J. S. Chung, “One-step synthesis of superior dispersion of chemically converted graphene in organic solvents,” Chem. Commun. (Camb.) 46(24), 4375–4377 (2010).
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F. Bonaccorso, A. Lombardo, T. Hasan, Z. P. Sun, L. Colombo, and A. C. Ferrari, “Production and processing of graphene and 2d crystals,” Mater. Today 15(12), 564–589 (2012).
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Y. B. Zhang, T. T. Tang, C. Girit, Z. Hao, M. C. Martin, A. Zettl, M. F. Crommie, Y. R. Shen, and F. Wang, “Direct observation of a widely tunable bandgap in bilayer graphene,” Nature 459(7248), 820–823 (2009).
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V. H. Pham, T. V. Cuong, T. D. Nguyen-Phan, H. D. Pham, E. J. Kim, S. H. Hur, E. W. Shin, S. Kim, and J. S. Chung, “One-step synthesis of superior dispersion of chemically converted graphene in organic solvents,” Chem. Commun. (Camb.) 46(24), 4375–4377 (2010).
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S. Y. Zhou, G. H. Gweon, A. V. Fedorov, P. N. First, W. A. de Heer, D. H. Lee, F. Guinea, A. H. Castro Neto, and A. Lanzara, “Substrate-induced bandgap opening in epitaxial graphene,” Nat. Mater. 6(10), 770–775 (2007).
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G. Eda, Y. Y. Lin, C. Mattevi, H. Yamaguchi, H. A. Chen, I. S. Chen, C. W. Chen, and M. Chhowalla, “Blue photoluminescence from chemically derived graphene oxide,” Adv. Mater. 22(4), 505–509 (2010).
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K. P. Loh, Q. Bao, G. Eda, and M. Chhowalla, “Graphene oxide as a chemically tunable platform for optical applications,” Nat. Chem. 2(12), 1015–1024 (2010).
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S. Y. Zhou, G. H. Gweon, A. V. Fedorov, P. N. First, W. A. de Heer, D. H. Lee, F. Guinea, A. H. Castro Neto, and A. Lanzara, “Substrate-induced bandgap opening in epitaxial graphene,” Nat. Mater. 6(10), 770–775 (2007).
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Ferrari, A. C.

F. Bonaccorso, A. Lombardo, T. Hasan, Z. P. Sun, L. Colombo, and A. C. Ferrari, “Production and processing of graphene and 2d crystals,” Mater. Today 15(12), 564–589 (2012).
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Z. Sun, T. Hasan, and A. C. Ferrari, “Ultrafast lasers mode-locked by nanotubes and graphene,” Physica E 44(6), 1082–1091 (2012).
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Z. P. Sun, D. Popa, T. Hasan, F. Torrisi, F. Q. Wang, E. J. R. Kelleher, J. C. Travers, V. Nicolosi, and A. C. Ferrari, “A stable, wideband tunable, near transform-limited, graphene-mode-locked, ultrafast laser,” Nano Res. 3(9), 653–660 (2010).
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F. Bonaccorso, Z. Sun, T. Hasan, and A. C. Ferrari, “Graphene photonics and optoelectronics,” Nat. Photonics 4(9), 611–622 (2010).
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Z. P. Sun, T. Hasan, F. Torrisi, D. Popa, G. Privitera, F. Q. Wang, F. Bonaccorso, D. M. Basko, and A. C. Ferrari, “Graphene mode-locked ultrafast laser,” ACS Nano 4(2), 803–810 (2010).
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T. Hasan, Z. P. Sun, F. Q. Wang, F. Bonaccorso, P. H. Tan, A. G. Rozhin, and A. C. Ferrari, “Nanotube-polymer composites for ultrafast photonics,” Adv. Mater. 21(38–39), 3874–3899 (2009).
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S. Y. Zhou, G. H. Gweon, A. V. Fedorov, P. N. First, W. A. de Heer, D. H. Lee, F. Guinea, A. H. Castro Neto, and A. Lanzara, “Substrate-induced bandgap opening in epitaxial graphene,” Nat. Mater. 6(10), 770–775 (2007).
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Gao, J. F.

L. Z. Liu, L. Wang, J. F. Gao, J. J. Zhao, X. F. Gao, and Z. F. Chen, “Amorphous structural models for graphene oxides,” Carbon 50(4), 1690–1698 (2012).
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Gao, X. F.

L. Z. Liu, L. Wang, J. F. Gao, J. J. Zhao, X. F. Gao, and Z. F. Chen, “Amorphous structural models for graphene oxides,” Carbon 50(4), 1690–1698 (2012).
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Y. B. Zhang, T. T. Tang, C. Girit, Z. Hao, M. C. Martin, A. Zettl, M. F. Crommie, Y. R. Shen, and F. Wang, “Direct observation of a widely tunable bandgap in bilayer graphene,” Nature 459(7248), 820–823 (2009).
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Gómez-Navarro, C.

C. Gómez-Navarro, R. T. Weitz, A. M. Bittner, M. Scolari, A. Mews, M. Burghard, and K. Kern, “Electronic transport properties of individual chemically reduced graphene oxide sheets,” Nano Lett. 7(11), 3499–3503 (2007).
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T. Remyamol, H. John, and P. Gopinath, “Synthesis and nonlinear optical properties of reduced graphene oxide covalently functionalized with polyaniline,” Carbon 59, 308–314 (2013).
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R. R. Nair, P. Blake, A. N. Grigorenko, K. S. Novoselov, T. J. Booth, T. Stauber, N. M. R. Peres, and A. K. Geim, “Fine structure constant defines visual transparency of graphene,” Science 320(5881), 1308 (2008).
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S. Y. Zhou, G. H. Gweon, A. V. Fedorov, P. N. First, W. A. de Heer, D. H. Lee, F. Guinea, A. H. Castro Neto, and A. Lanzara, “Substrate-induced bandgap opening in epitaxial graphene,” Nat. Mater. 6(10), 770–775 (2007).
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Gweon, G. H.

S. Y. Zhou, G. H. Gweon, A. V. Fedorov, P. N. First, W. A. de Heer, D. H. Lee, F. Guinea, A. H. Castro Neto, and A. Lanzara, “Substrate-induced bandgap opening in epitaxial graphene,” Nat. Mater. 6(10), 770–775 (2007).
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E. Hendry, P. J. Hale, J. Moger, A. K. Savchenko, and S. A. Mikhailov, “Coherent nonlinear optical response of graphene,” Phys. Rev. Lett. 105(9), 097401 (2010).
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Hao, Z.

Y. B. Zhang, T. T. Tang, C. Girit, Z. Hao, M. C. Martin, A. Zettl, M. F. Crommie, Y. R. Shen, and F. Wang, “Direct observation of a widely tunable bandgap in bilayer graphene,” Nature 459(7248), 820–823 (2009).
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Hasan, T.

Z. Sun, T. Hasan, and A. C. Ferrari, “Ultrafast lasers mode-locked by nanotubes and graphene,” Physica E 44(6), 1082–1091 (2012).
[CrossRef]

F. Bonaccorso, A. Lombardo, T. Hasan, Z. P. Sun, L. Colombo, and A. C. Ferrari, “Production and processing of graphene and 2d crystals,” Mater. Today 15(12), 564–589 (2012).
[CrossRef]

F. Bonaccorso, Z. Sun, T. Hasan, and A. C. Ferrari, “Graphene photonics and optoelectronics,” Nat. Photonics 4(9), 611–622 (2010).
[CrossRef]

Z. P. Sun, T. Hasan, F. Torrisi, D. Popa, G. Privitera, F. Q. Wang, F. Bonaccorso, D. M. Basko, and A. C. Ferrari, “Graphene mode-locked ultrafast laser,” ACS Nano 4(2), 803–810 (2010).
[CrossRef] [PubMed]

Z. P. Sun, D. Popa, T. Hasan, F. Torrisi, F. Q. Wang, E. J. R. Kelleher, J. C. Travers, V. Nicolosi, and A. C. Ferrari, “A stable, wideband tunable, near transform-limited, graphene-mode-locked, ultrafast laser,” Nano Res. 3(9), 653–660 (2010).
[CrossRef]

T. Hasan, Z. P. Sun, F. Q. Wang, F. Bonaccorso, P. H. Tan, A. G. Rozhin, and A. C. Ferrari, “Nanotube-polymer composites for ultrafast photonics,” Adv. Mater. 21(38–39), 3874–3899 (2009).
[CrossRef]

Heinz, T. F.

K. F. Mak, M. Y. Sfeir, Y. Wu, C. H. Lui, J. A. Misewich, and T. F. Heinz, “Measurement of the optical conductivity of graphene,” Phys. Rev. Lett. 101(19), 196405 (2008).
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Hendry, E.

E. Hendry, P. J. Hale, J. Moger, A. K. Savchenko, and S. A. Mikhailov, “Coherent nonlinear optical response of graphene,” Phys. Rev. Lett. 105(9), 097401 (2010).
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Hur, S. H.

V. H. Pham, T. V. Cuong, T. D. Nguyen-Phan, H. D. Pham, E. J. Kim, S. H. Hur, E. W. Shin, S. Kim, and J. S. Chung, “One-step synthesis of superior dispersion of chemically converted graphene in organic solvents,” Chem. Commun. (Camb.) 46(24), 4375–4377 (2010).
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Jiang, X. F.

X. F. Jiang, L. Polavarapu, S. T. Neo, T. Venkatesan, and Q. H. Xu, “Graphene oxides as tunable broadband nonlinear optical materials for femtosecond laser pulses,” J. Phys. Chem. Lett. 3(6), 785–790 (2012).
[CrossRef]

John, H.

T. Remyamol, H. John, and P. Gopinath, “Synthesis and nonlinear optical properties of reduced graphene oxide covalently functionalized with polyaniline,” Carbon 59, 308–314 (2013).
[CrossRef]

Jung, I. W.

S. Park, J. H. An, I. W. Jung, R. D. Piner, S. J. An, X. S. Li, A. Velamakanni, and R. S. Ruoff, “Colloidal suspensions of highly reduced graphene oxide in a wide variety of organic solvents,” Nano Lett. 9(4), 1593–1597 (2009).
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Kelleher, E. J. R.

Z. P. Sun, D. Popa, T. Hasan, F. Torrisi, F. Q. Wang, E. J. R. Kelleher, J. C. Travers, V. Nicolosi, and A. C. Ferrari, “A stable, wideband tunable, near transform-limited, graphene-mode-locked, ultrafast laser,” Nano Res. 3(9), 653–660 (2010).
[CrossRef]

Kern, K.

C. Gómez-Navarro, R. T. Weitz, A. M. Bittner, M. Scolari, A. Mews, M. Burghard, and K. Kern, “Electronic transport properties of individual chemically reduced graphene oxide sheets,” Nano Lett. 7(11), 3499–3503 (2007).
[CrossRef] [PubMed]

Kim, E. J.

V. H. Pham, T. V. Cuong, T. D. Nguyen-Phan, H. D. Pham, E. J. Kim, S. H. Hur, E. W. Shin, S. Kim, and J. S. Chung, “One-step synthesis of superior dispersion of chemically converted graphene in organic solvents,” Chem. Commun. (Camb.) 46(24), 4375–4377 (2010).
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Kim, S.

V. H. Pham, T. V. Cuong, T. D. Nguyen-Phan, H. D. Pham, E. J. Kim, S. H. Hur, E. W. Shin, S. Kim, and J. S. Chung, “One-step synthesis of superior dispersion of chemically converted graphene in organic solvents,” Chem. Commun. (Camb.) 46(24), 4375–4377 (2010).
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Kovsh, D. I.

Lanzara, A.

S. Y. Zhou, G. H. Gweon, A. V. Fedorov, P. N. First, W. A. de Heer, D. H. Lee, F. Guinea, A. H. Castro Neto, and A. Lanzara, “Substrate-induced bandgap opening in epitaxial graphene,” Nat. Mater. 6(10), 770–775 (2007).
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Lee, D. H.

S. Y. Zhou, G. H. Gweon, A. V. Fedorov, P. N. First, W. A. de Heer, D. H. Lee, F. Guinea, A. H. Castro Neto, and A. Lanzara, “Substrate-induced bandgap opening in epitaxial graphene,” Nat. Mater. 6(10), 770–775 (2007).
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Li, J.

Y. Shen, P. Zhou, Q. Q. Sun, L. Wan, J. Li, L. Y. Chen, D. W. Zhang, and X. B. Wang, “Optical investigation of reduced graphene oxide by spectroscopic ellipsometry and the band-gap tuning,” Appl. Phys. Lett. 99(14), 141911 (2011).
[CrossRef]

Li, X. C.

Li, X. S.

S. Park, J. H. An, I. W. Jung, R. D. Piner, S. J. An, X. S. Li, A. Velamakanni, and R. S. Ruoff, “Colloidal suspensions of highly reduced graphene oxide in a wide variety of organic solvents,” Nano Lett. 9(4), 1593–1597 (2009).
[CrossRef] [PubMed]

Lin, Y. Y.

G. Eda, Y. Y. Lin, C. Mattevi, H. Yamaguchi, H. A. Chen, I. S. Chen, C. W. Chen, and M. Chhowalla, “Blue photoluminescence from chemically derived graphene oxide,” Adv. Mater. 22(4), 505–509 (2010).
[CrossRef] [PubMed]

Liu, L. Z.

L. Z. Liu, L. Wang, J. F. Gao, J. J. Zhao, X. F. Gao, and Z. F. Chen, “Amorphous structural models for graphene oxides,” Carbon 50(4), 1690–1698 (2012).
[CrossRef]

Liu, Z. B.

X. L. Zhang, Z. B. Liu, X. C. Li, Q. Ma, X. D. Chen, J. G. Tian, Y. F. Xu, and Y. S. Chen, “Transient thermal effect, nonlinear refraction and nonlinear absorption properties of graphene oxide sheets in dispersion,” Opt. Express 21(6), 7511–7520 (2013).
[CrossRef] [PubMed]

X. L. Zhang, X. Zhao, Z. B. Liu, S. Shi, W. Y. Zhou, J. G. Tian, Y. F. Xu, and Y. S. Chen, “Nonlinear optical and optical limiting properties of graphene oxide-fe3o4 hybrid material,” J. Opt. 13(7), 075202 (2011).
[CrossRef]

Z. B. Liu, Y. Wang, X. L. Zhang, Y. F. Xu, Y. S. Chen, and J. G. Tian, “Nonlinear optical properties of graphene oxide in nanosecond and picosecond regimes,” Appl. Phys. Lett. 94(2), 021902 (2009).
[CrossRef]

Liu, Z.-B.

Z.-B. Liu, X. Zhao, X.-L. Zhang, X.-Q. Yan, Y.-P. Wu, Y.-S. Chen, and J.-G. Tian, “Ultrafast dynamics and nonlinear optical responses from sp2- and sp3-hybridized domains in graphene oxide,” J. Phys. Chem. Lett. 2(16), 1972–1977 (2011).
[CrossRef]

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K. P. Loh, Q. Bao, G. Eda, and M. Chhowalla, “Graphene oxide as a chemically tunable platform for optical applications,” Nat. Chem. 2(12), 1015–1024 (2010).
[CrossRef] [PubMed]

Lombardo, A.

F. Bonaccorso, A. Lombardo, T. Hasan, Z. P. Sun, L. Colombo, and A. C. Ferrari, “Production and processing of graphene and 2d crystals,” Mater. Today 15(12), 564–589 (2012).
[CrossRef]

Lui, C. H.

K. F. Mak, M. Y. Sfeir, Y. Wu, C. H. Lui, J. A. Misewich, and T. F. Heinz, “Measurement of the optical conductivity of graphene,” Phys. Rev. Lett. 101(19), 196405 (2008).
[CrossRef] [PubMed]

Ma, Q.

Mak, K. F.

K. F. Mak, M. Y. Sfeir, Y. Wu, C. H. Lui, J. A. Misewich, and T. F. Heinz, “Measurement of the optical conductivity of graphene,” Phys. Rev. Lett. 101(19), 196405 (2008).
[CrossRef] [PubMed]

Martin, M. C.

Y. B. Zhang, T. T. Tang, C. Girit, Z. Hao, M. C. Martin, A. Zettl, M. F. Crommie, Y. R. Shen, and F. Wang, “Direct observation of a widely tunable bandgap in bilayer graphene,” Nature 459(7248), 820–823 (2009).
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A. Martinez and Z. P. Sun, “Nanotube and graphene saturable absorbers for fibre lasers,” Nat. Photonics 7(11), 842–845 (2013).
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Mattevi, C.

G. Eda, Y. Y. Lin, C. Mattevi, H. Yamaguchi, H. A. Chen, I. S. Chen, C. W. Chen, and M. Chhowalla, “Blue photoluminescence from chemically derived graphene oxide,” Adv. Mater. 22(4), 505–509 (2010).
[CrossRef] [PubMed]

Mews, A.

C. Gómez-Navarro, R. T. Weitz, A. M. Bittner, M. Scolari, A. Mews, M. Burghard, and K. Kern, “Electronic transport properties of individual chemically reduced graphene oxide sheets,” Nano Lett. 7(11), 3499–3503 (2007).
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Mikhailov, S. A.

E. Hendry, P. J. Hale, J. Moger, A. K. Savchenko, and S. A. Mikhailov, “Coherent nonlinear optical response of graphene,” Phys. Rev. Lett. 105(9), 097401 (2010).
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K. F. Mak, M. Y. Sfeir, Y. Wu, C. H. Lui, J. A. Misewich, and T. F. Heinz, “Measurement of the optical conductivity of graphene,” Phys. Rev. Lett. 101(19), 196405 (2008).
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Moger, J.

E. Hendry, P. J. Hale, J. Moger, A. K. Savchenko, and S. A. Mikhailov, “Coherent nonlinear optical response of graphene,” Phys. Rev. Lett. 105(9), 097401 (2010).
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R. R. Nair, P. Blake, A. N. Grigorenko, K. S. Novoselov, T. J. Booth, T. Stauber, N. M. R. Peres, and A. K. Geim, “Fine structure constant defines visual transparency of graphene,” Science 320(5881), 1308 (2008).
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Negusse, E.

S. Saxena, T. A. Tyson, S. Shukla, E. Negusse, H. Y. Chen, and J. M. Bai, “Investigation of structural and electronic properties of graphene oxide,” Appl. Phys. Lett. 99(1), 013104 (2011).
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X. F. Jiang, L. Polavarapu, S. T. Neo, T. Venkatesan, and Q. H. Xu, “Graphene oxides as tunable broadband nonlinear optical materials for femtosecond laser pulses,” J. Phys. Chem. Lett. 3(6), 785–790 (2012).
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V. H. Pham, T. V. Cuong, T. D. Nguyen-Phan, H. D. Pham, E. J. Kim, S. H. Hur, E. W. Shin, S. Kim, and J. S. Chung, “One-step synthesis of superior dispersion of chemically converted graphene in organic solvents,” Chem. Commun. (Camb.) 46(24), 4375–4377 (2010).
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Z. P. Sun, D. Popa, T. Hasan, F. Torrisi, F. Q. Wang, E. J. R. Kelleher, J. C. Travers, V. Nicolosi, and A. C. Ferrari, “A stable, wideband tunable, near transform-limited, graphene-mode-locked, ultrafast laser,” Nano Res. 3(9), 653–660 (2010).
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R. R. Nair, P. Blake, A. N. Grigorenko, K. S. Novoselov, T. J. Booth, T. Stauber, N. M. R. Peres, and A. K. Geim, “Fine structure constant defines visual transparency of graphene,” Science 320(5881), 1308 (2008).
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Figures (7)

Fig. 1
Fig. 1

The GO and RGO dispersions used in this study.

Fig. 2
Fig. 2

XPS spectra of samples GO, RGO0.45, RGO1, and RGO4. Peaks are (1) C-C, (2)C-N, (3)C-OH, (4)C = O, (5)O = C-OH.

Fig. 3
Fig. 3

Raman spectra of the four samples under study. The ratio between D band and G band increases from 0.87 to 1.13 as the degree of reduction increases.

Fig. 4
Fig. 4

UV-vis spectrum of spray-coated samples. The main absorption peak shows a redshift from 231 nm to 257 nm upon reduction. All curves are normalized to maximum peak absorbance.

Fig. 5
Fig. 5

Open aperture Z-scan curves of GO and RGO samples measured at different pulse energy. The symbols represent experimental data and the solid lines are the results from our simulations.

Fig. 6
Fig. 6

Linear absorbance, saturation intensiy, and TPA coefficents of the GO and RGO samples as a function of C/O ratio. Open triangles represent TPA coefficents measured at different pulse energy. The average of the data is given by the solid line as a guide to the eye.

Fig. 7
Fig. 7

Structure and band diagram of RGO. The left cartoon (a) illustrates the three regions present in RGO: sp3 matrix, sp2 cluster and sp2 domain. It should be noted that there are no sp2 domains in GO, but the sp3 matrix and sp2 clusters are almost identical to those in RGO. The right hand side (b) illustrates the band gap of the three regions in RGO (pink and blue represent conduction and valence band, respectively). For sp3 matrix and sp2 cluster, the band gap are about 6eV and 0.5eV, respectively. The band gap of sp2 domains varies from 6 eV to 0.5 eV, depending on their size. The photon energy used was 2.3 eV (532 nm). Single and TPA routes are illustrated by green arrows. Single photon absorption exists in sp2 clusters while two photon absorption exists in the sp3 matrix. Both single and TPA exist in sp2 domains.

Tables (1)

Tables Icon

Table 1 Characteristics of our four samples. The chemical bond and element composition have been obtained from XPS spectra. Oxygen-containing groups are partially removed while C-N bonds arise after reduction. The D/G band ratios (ID/IG) and π-π* absorption peak positions are measured from Raman and UV-vis absorption spectra respectively. The TPA coefficient (β) and saturation intensity (Is) obtained from Z-scan experiments are also listed.

Equations (4)

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2jk E z =( 2 r 2 + 1 r r + k 0 2 χ NL ' ( r,z ) )E
χ NL ' ( r,z )=2 n 0 Δn( r,z )j n 0 k 0 α Δn= n 2 I α= α 0 1+ I I s +βI
α G O ( I ) = N c σ c 0 1 + I I s c + N m σ m T P A I = α 0 G O 1 + I I s G O + β G O I α R G O ( I ) = N c σ c 0 1 + I I s c + f N m σ d 0 1 + I I s d + ( 1 f ) N m σ m T P A I + f N m σ d T P A I = α 0 R G O 1 + I I s R G O + β R G O I
α 0 GO = N c σ c 0 I s GO = I sc α 0 RGO = N c σ c 0 +f N m σ d 0 N c σ c 0 ( 1 I sc 1 I s RGO )=f N m σ d 0 ( 1 I s RGO 1 I sd )

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