Terahertz electrical conductivity and optical characterization of composite nonaligned single- and multiwalled carbon nanotubes

Dadrasnia, Ehsan; Puthukodan, Sujitha; Lamela, Horacio

doi:10.1117/1.jnp.8.083099

Cited by 34 publications

(23 citation statements)

References 41 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…[215][216][217][218][219][220] Zhang et al [221] studied metallic and doped semiconductor SW CNTs films and demonstrated that the frequently observed localized response (or the so-called conductivity peak at finite frequency in the THz spectra) is due to a localized plasmon related to a finite length of the CNTs and their nonpercolation. The samples are usually prepared as self-standing films or films supported by a substrate.…”

Section: Thz Response Of Carbon Nanotubesmentioning

confidence: 99%

“…In a number of papers the THz conductivity of samples with nonaligned, partially aligned or completely aligned CNTs was interpreted within a Maxwell-Garnett effective medium model for composites with the intrinsic CNT conductivity described by a Drude term (to account for metallic nanotubes) and a harmonic oscillator term (to account for undoped semiconductor nanotubes). [215][216][217][218][219][220] Zhang et al [221] studied metallic and doped semiconductor SW CNTs films and demonstrated that the frequently observed localized response (or the so-called conductivity peak at finite frequency in the THz spectra) is due to a localized plasmon related to a finite length of the CNTs and their nonpercolation. In other words, the response can be described by an effective medium theory.…”

Section: Thz Response Of Carbon Nanotubesmentioning

confidence: 99%

See 1 more Smart Citation

Terahertz Spectroscopy of Nanomaterials: a Close Look at Charge‐Carrier Transport

Kužel

Němec

2019

Advanced Optical Materials

View full text Add to dashboard Cite

Transport of charges is a fundamental process in many high-tech applications including photovoltaic or optoelectronic devices, but also in more ordinary components such as unsophisticated wires and other circuitry. The development of nanotechnologies resulted in the fabrication of highly complex materials consisting of a large variety of nanosized elements, which inevitably involve a multitude of charge transport processes occurring on various time-and length-scales. Figure 1 summarizes the most common nanoelements with high application potential.For example, the electrodes employed in Grätzel solar cells [1] are composed of percolated networks of a huge number of metal oxide nanoparticles (top-left panel in Figure 1). Colloidal nanocrystals form the basis for thin film electronics and flexible electronic devices. [2] The synthetic approaches control their composition, size and electronic structure (energy levels, density of states within the bands and in the bandgap) and the charge-carrier transport. [2,3] Nanowires and nanotubes made of conventional semiconductors are quasi 1D systems combining Terahertz spectroscopy has been used for almost two decades for investigations of nanomaterials, including nanocrystals, nanoparticles, nanowires, nanotubes or 2D crystals. Its great importance stems from the fact that it is a noncontact method and, owing to its high frequency and broadband character, it is capable of characterizing charge transport properties within individual nano-objects but also among them. In addition, probing of photoinitiated ultrafast charge dynamics is possible thanks to the sub-picosecond time resolution. Despite this unprecedented potential, the interpretation of the measured terahertz conductivity spectra in many materials is still intensively debated. Herein is presented a review of the experiments performed on nanostructures of conventional semiconductors and on carbon nanomaterials (graphene and carbon nanotubes) during the past decade. The state of the art of the theoretical formalism is provided and discussed, including the intrinsic response, as well as the role of inherent heterogeneity and of the experimental conditions.

show abstract

Section: Thz Response Of Carbon Nanotubesmentioning

confidence: 99%

Section: Thz Response Of Carbon Nanotubesmentioning

confidence: 99%

Terahertz Spectroscopy of Nanomaterials: a Close Look at Charge‐Carrier Transport

Kužel

Němec

2019

Advanced Optical Materials

View full text Add to dashboard Cite

show abstract

“…The THz responses of the samples have been characterized using a conventional THz-TDS setup [22,23]. The samples are located at the waist of the THz beam: at any frequency of the available THz signal, the Rayleigh length of the beam is much larger than the bare or covered substrate; therefore, the sample can be considered as illuminated at normal incidence by a plane wave.…”

Section: Time-domain Spectroscopy and Thz Signalsmentioning

confidence: 99%

Determination of the DC Electrical Conductivity of Multiwalled Carbon Nanotube Films and Graphene Layers from Noncontact Time-Domain Terahertz Measurements

Dadrasnia

Lamela

Kuppam

et al. 2014

Advances in Condensed Matter Physics

View full text Add to dashboard Cite

Measuring the DC conductivity of very thin films could be rather difficult because of the electrical contact issue. This DC conductivity can, however, be extracted from noncontact measurements at GHz and THz frequencies using elaborated conductivity models that nicely fit the experimental data. Here we employ this technique to study the DC conductivity of fragile nanometer-thick films of multiwalled carbon nanotubes and monolayer graphene. The THz response of the films is measured by THz time-domain spectroscopy. We show that the THz conductivity of the samples is well fitted by either Drude-Lorentz model or Drude-Smith model, giving information on the physics of electrical conductivity in these materials. This extraction procedure is validated by the good agreement between the so-obtained DC conductivity and the one measured with a classical 4-point probe in-line contact method.

show abstract

“…For higher frequencies, there are some fluctuations due to the insufficient THz power. From these data, the conductivity of the films is determined using relation (2). It is important to note that, in the THz range, absorption through intraband transitions dominates the one related to interband transitions, 29 and thus intraband absorption influences mainly the THz conductivity.…”

mentioning

confidence: 99%

Electrical characterization of silver nanowire-graphene hybrid films from terahertz transmission and reflection measurements

Dadrasnia

Garet

Lee

et al. 2014

Applied Physics Letters

Self Cite

View full text Add to dashboard Cite

We determined the electrical sheet conductivity of silver nanowire-graphene hybrid films from transmission and reflection terahertz time-domain spectroscopy measurements. The sheet resistance extracted from noncontact terahertz measurement is in good agreement with one measured with a classical 4-point-probe technique. The conductivity is well described by a Drude-Smith model and is calculated to peak around 10 THz.

show abstract

Terahertz electrical conductivity and optical characterization of composite nonaligned single- and multiwalled carbon nanotubes

Cited by 34 publications

References 41 publications

Terahertz Spectroscopy of Nanomaterials: a Close Look at Charge‐Carrier Transport

Terahertz Spectroscopy of Nanomaterials: a Close Look at Charge‐Carrier Transport

Determination of the DC Electrical Conductivity of Multiwalled Carbon Nanotube Films and Graphene Layers from Noncontact Time-Domain Terahertz Measurements

Electrical characterization of silver nanowire-graphene hybrid films from terahertz transmission and reflection measurements

Contact Info

Product

Resources

About