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The discovery of High Critical Temperature Superconductors (HTS) generated great activity to develop dc Superconductive Quantum Interference Devices (SQUIDs), with operating temperatures up to the boiling point of liquid nitrogen, 77. K.It was immediately apparent that small-scale devices, like SQUIDs, would require the development of thin-film techniques and novel Josephson junction's fabrication technologies. At present, grain-boundary junctions are the most widely used in SQUIDs. However, their properties are strongly affected by the d-wave symmetry of the order parameter. As a consequence the static and dynamic properties of HTS SQUIDs can be profoundly modified. The d-wave symmetry also offers the possibility to design π-SQUIDs showing a complementary behavior in magnetic field, compared to conventional ones, as well as dc SQUIDs with a double well potential. In this chapter the new Josephson phenomenology of HTS SQUIDs is derived, compared with experimental data available in literature, and discussed in view of future novel applications. © 2011 Woodhead Publishing Limited All rights reserved.

A classical many-body model for the phase dynamics of randomly pinned charge density waves is found to exhibit stretched exponential relaxation below threshold. The statistics of single particle relaxation is highly non-trivial and can only be deduced from known scaling behaviour of intermittent trajectories in an uncoupled approximation. This is compared with results from present single-particle approaches. The self-similarity properties at the dynamical phase transition at threshold are investigated.

The amplitude envelope of speech carries crucial low-frequency acoustic information that assists linguistic decoding at multiple time scales. Neurophysiological signals are known to track the amplitude envelope of adult-directed speech (ADS), particularly in the theta-band. Acoustic analysis of infant-directed speech (IDS) has revealed significantly greater modulation energy than ADS in an amplitude-modulation (AM) band centered on ∼2 Hz. Accordingly, cortical tracking of IDS by delta-band neural signals may be key to language acquisition. Speech also contains acoustic information within its higher-frequency bands (beta, gamma). Adult EEG and MEG studies reveal an oscillatory hierarchy, whereby low-frequency (delta, theta) neural phase dynamics temporally organize the amplitude of high-frequency signals (phase amplitude coupling, PAC). Whilst consensus is growing around the role of PAC in the matured adult brain, its role in the development of speech processing is unexplored.Here, we examined the presence and maturation of low-frequency (Graphical abstractHighlightsLongitudinal EEG study in which 4, 7- & 11-month infants listened to nursery rhymesWe demonstrate cortical speech tracking via delta & theta neural signals (mTRF)Periodogram (PSD) analysis revealed stimulus related delta & theta PSD peaksDelta and theta driven phase amplitude coupling (PAC) was found at all agesGamma frequency amplitudes displayed stronger PAC to low frequency phases than beta

Optical micromanipulation is a powerful and versatile technique based upon the light–matter interaction. Whilst the forces exerted by optical traps are naturally very small, they are sufficient to realize non-invasive mechanical control over mesoscopic particles within atomic, biological and colloidal systems. The inherent compatibility with modern microscopy enhances the reconfigurability of the trap while the accuracy achieved in a calibrated optical trap presents itself as a quantitative force probe. Thus forces can be applied in a controlled manner to biological systems including cells and molecular motors and processes measured with high precision. The impact is not limited to biology. Optical traps have provided seminal studies in colloidal and optical physics including the phase dynamics of thermodynamic systems, Brownian diffusion, aspects of microfluidics, and fundamental issues related to optical angular momentum. This article aims to focus upon the emergent theme of optical trappingOptical trapping with structured light fields. By structured light fields we refer to the generation of multiple arrays of traps and the use of specialist light fields such as Laguerre-Gaussian beams and Bessel beams. Structured light fields are making a major impact on optical trappingOptical trapping and on subsequent applications including those in biomedicine.