Charge modulation spectroscopy ͑CMS͒ is an electro-optical spectroscopic technique that allows the charge carriers present in the conducting channels of field-effect transistors ͑FET's͒ to be studied in situ. We use this technique to study the charge carriers present in regio-regular poly͑3-hexylthiophene͒ P3HT that has been shown to exhibit high field-effect mobilities of up to 0.1 cm 2 /Vs, similar to that observed for amorphous silicon. We demonstrate that the CMS spectra of charge carriers in high-mobility regio-regular P3HT FET's are independent of charge density, modulation frequency, and temperature. This is evidence for the presence of a single, intrinsic charge carrier that we identify as a singly charged polaronic species. The spectral features attributed to the charged species show a lack of vibronic structure that is in contrast to the vibronic structure present in the bleaching of the main -* absorption of the neutral chains. The transition energies observed in regio-regular P3HT cannot be understood as an extrapolation of charge-induced transitions in isolated short-chain oligomers to long conjugation lengths. Our results give evidence that interchain coupling in highly ordered P3HT is sufficiently strong so that the charge carriers cannot be considered to be confined to a single chain, rather, they now exhibit quasi-two-dimensional characteristics.

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We have measured the photocurrent action spectra of the conjugated polymers poly͓2-methoxy, 5 ethyl ͑2Ј hexyloxy͒ paraphenylenevinylene͔ ͑MEH-PPV͒ and poly͑phenylenevinylene͒ ͑PPV͒ in sandwich cells between indium tin oxide ͑ITO͒ and aluminum electrodes. Under forward bias and illumination through ITO, the photocurrent spectrum is broad and has a maximum at high energy, where the absorption coefficient is greatest ͑the symbatic response͒. Under reverse bias and illumination through ITO, the photocurrent spectrum consists of a very narrow peak ͑the full width at half maximum is 0.1 eV͒, located in the low-energy tail of the absorption profile ͑the antibatic response͒. Several established models attempt to explain this behavior and to relate the photocurrent action spectrum to the absorption coefficient, considering penetration depth of the light and diffusion of excitons or directly photogenerated charges. At a qualitative level many of these seem to provide an adequate description. In this paper, we undertake a quantitative examination of these models and we find that none of them can reproduce the very narrow antibatic response that we observe in both MEH-PPV and PPV. Upon exposure to air, we observe an enhancement of the photocurrent by a much greater factor than the dark current, from which we conclude that charge generation is mediated by exciton dissociation. As the temperature decreases we observe a progressive redshift of the absorption edge, although the photocurrent onset undergoes a much smaller redshift. We therefore conclude that the narrow antibatic peak is due to a specific enhancement of dissociation upon excitation at low energy. We propose that the particularly sharp onset of photocurrent at low energy may be due to enhanced intermolecular charge separation within crystallite grains between those neighboring conjugated segments that are more extended and more planar.

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IoS is denoting a software based component that will be delivered via different networks and Internet. Research on SOA, Web/Enterprise 3.0/X.0, Enterprise Interoperability, Service Web, Grid Services and Semantic Web will address important bits of the IoS puzzle, while improving cooperation between service providers and consumers.IoM will address the challenges in scalable video coding and 3D video processing, dynamically adapted to the network conditions that will give rise to innovative applications such as massive multiplayer mobile games, digital cinema and in virtual worlds placing new types of traffic demands on mobile network architectures.This future network of networks will be laid out as public/private infrastructures and dynamically extended and improved by edge points created by the "things" connecting to one another. In fact, in the IoT communications will take place not only between people but also between people and their environment.Communication will be seen more among terminals and data centres (e.g. home data centres, Cloud computing, etc) than among nodes as in current networks. Growth of storage capacity at lower and lower costs will result in the local availability of most information required by people or objects. This, coupled with the enhanced processing capabilities and always-on connectivity, will make terminals gain a main role in communications.Terminals will be able to create a local communication network and may serve as a bridge between communication networks thus extending, particularly in urban environments, the overall infrastructure capacity. This will likely determine a different view of network architectures. The Future Internet will exhibit high levels of heterogeneity ("things"physical/real, cyber physical, web enabled, digital and virtual, devices and device models, communication protocols, cognitive capabilities, etc.), as totally different things, in terms of functionality, technology and application fields are expected to belong to the same communication environment.Many colleagues have assisted with their views on this Internet of Things strategic research agenda document. Their contributions are gratefully acknowledged.