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Terahertz band has recently attracted the attention of the communication society due to its huge bandwidth and very high-speed wireless communications capability. It has been utilized in a variety of disciplines including physics, biology and astronomy for years; and the main concerns have always been obtaining highly efficient and high-power terahertz sources. Today, these problems are still the most important issues in establishing an operable wireless terahertz communication link. In this paper, recent studies in the field of terahertz source design are investigated based on the terahertz output power and efficiency. Solid-state sources and optical sources were comparatively reviewed with optical photoconductive material (OPM)-based methods which are combined with the terahertz antennas in the design phase generally. For wireless communication, the most suitable frequencies are between 0.3THz and 1THz due to the attenuation profile of the atmosphere. For this reason, based on the recently published studies, it has been observed that OPM and resonant tunneling diode-based sources are the most promising terahertz sources in terms of efficiency and power. Key issues and the main problems of terahertz photoconductive antennas which are the base of OPM method were also discussed in this paper.

This paper describes state-of-the-art of high-speed electronic device and IC technologies for very high-speed lightwave communications systems. The technology of interest is for over 40-Gbit/s transmitter and receiver operations. Device technology including Si-Ge, GaAs-based, and InP-based heterostructure transistors as well as circuit design technology including analog/digital/mixed-signal and optoelectronic IC's are reviewed. The speed limiting factors are discussed to address the future trends toward 100 Gbit/s and beyond.

In the recent decades of high energy physics research, it was demonstrated that strongly interacting quark-gluon plasma (sQGP) is created in ultra-relativistic nucleus–nucleus collisions. Investigation and understanding of properties of the hadronic matter is among the important goals of NA61/SHINE collaboration at CERN SPS. Mapping of the phase diagram is achieved by varying the collision energy ($5\mathrm{\text{GeV}}<\sqrt{s_{\mathrm{\text{NN}}}}<17\mathrm{\text{GeV}}$) and by changing the collision system ($\mathrm{\text{p}}+\mathrm{\text{p}}$, $\mathrm{\text{p}}+\mathrm{\text{Pb}}$, $\mathrm{\text{Be}}+\mathrm{\text{Be}}$, $\mathrm{\text{Ar}}+\mathrm{\text{Sc}}$, $\mathrm{\text{Xe}}+\mathrm{\text{La}}$, $\mathrm{\text{Pb}}+\mathrm{\text{Pb}}$).

We report on the measurement of femtoscopic correlations in intermediate systems at intermediate SPS energies. Interpreting the results of measurements within the symmetric Lévy source formalism, we discuss the values of Lévy source parameters as a function of average pair transverse mass. One of the physical parameters is particularly important, the Lévy exponent $\alpha$, which describes the shape of the source and may be related to the critical exponent $\eta$ in the proximity of the critical point. Therefore, measuring it may shed light on the location of the critical endpoint of the QCD phase diagram.