Nonlinear optical absorption and reflection of single wall carbon nanotube thin films by Z-scan technique

Abstract

Both the nonlinear optical transmission and reflection characteristics of HiPco-based single wall carbon nanotube (SWNT) thin films are studied by using the Z-scan method with femtosecond laser pulses at a wavelength of 1.46 μm. The nonlinear absorption coefficient and nonlinear refractive index are obtained as (5.4 ± 2.0) × 10 −7 cm/W and (1.1 ± 0.5) × 10 −11 cm 2 /W, respectively, which are considerably greater than those of other optical materials. This large optical nonlinearity is ascribed to (a) homogeneously deposited thin nanotube film on optically transparent barium fluoride, (b) just-resonant excitation condition, and (c) intrinsic saturable absorption feature of SWNTs.

Nanotube–Polymer Composites for Ultrafast Photonics

“…Z-Scan and Power-Dependent Transmission Z-scan experiments probe the optical nonlinearities associated with the change in refraction and absorption coefficient induced by intense laser power. [84,185,[307][308][309][310] The material is moved along the waist of a Gaussian beam, as shown in Figure 9a. This results in a variation of the laser-power density on the sample, which reaches its maximum at the focal point.…”

Nonlinear optics of nontoxic nanomaterials

“…CNTs are all-carbon hollow graphite nanomaterials with a high aspect ratio, length ranging from several hundred nanometers to few micrometers and diameter of less than nanometer to tens of nanometers. The nonlinear optical characteristics of CNTs have been extensively studied as suspension in solution [2], in polymer films [3][4][5], and sprayed on optically transparent substrates [6]. Semiconductor nanoparticles, nanowires and nanorods are also widely investigated due to their strong nonlinear absorption, refraction, and scattering properties [7][8][9].…”

“…However, there are no reports on their optical properties. The halloysite was used in the thin film assembly by alternate adsorption with poly(ethyleneimine) (PEI), that resulted in formation of ordered multilayers (2)(3)(4)(5)(6)(7)(8)(9)(10)(11)(12)(13)(14)(15)(16)(17)(18)(19)(20) of clay tubules glued together by polycation interlayers [16]. The interior lumen of the halloysite has been used as an enzymatic nanoscale reactor [17].…”

Ultrafast electron dynamics and cubic optical nonlinearity of freestanding thin film of double walled carbon nanotubes

“…Recent z-scan measurements 25 at 1.57 eV showed Im͑ ͑3͒ ͒ =10 −9 esu and Re͑ ͑3͒ ͒ = −4.4ϫ 10 −9 esu for SWNT suspensions ͑using a surfactant͒ and Im͑ ͑3͒ ͒ =8 ϫ 10 −9 esu and Re͑ ͑3͒ ͒ = 1.4ϫ 10 −8 esu at 0.85 eV for SWNT thin films. 26 In the case of multiwalled CNTs ͑MWNT͒ grown on a quartz substrate, 27 the values are Im͑ ͑3͒ ͒ = −1.6ϫ 10 −11 esu and Re͑ ͑3͒ ͒ = −1.7ϫ 10 −11 esu, and photobleaching ͑PB͒ decay time of ϳ2 ps was reported. As compared to SWNT and MWNT, double walled CNTs ͑DWNT͒ have not been investigated for their nonlinear properties, except the work of Nakamura et al, 28 where pumpprobe ͑PP͒ studies show PB with biexponential relaxation for DWNT suspensions.…”