Market Power and Collusion on Interconnection Phone Market in Tunisia : What Lessons from International Experiences

We try in this paper to characterize the state of mobile phone market in Tunisia. Our study is based on a survey of foreign experience (Europe) in detecting collusive behavior and a comparison of the critical threshold of collusion between operators in developing countries like Tunisia. The market power is estimated based on the work of Parker Roller (1997) and the assumption of "Balanced Calling Pattern". We use then the model of Friedman (1971) to compare the critical threshold of collusion. We show that the "conduct parameter" measuring the intensity of competition is not null during the period 1993-2011. Results show also that collusion is easier on the Tunisian market that on the Algerian, Jordanian, or Moroccan one

Phonon-driven spin-Floquet magneto-valleytronics in MoS2

Two-dimensional materials equipped with strong spin-orbit coupling can display novel electronic, spintronic, and topological properties originating from the breaking of time or inversion symmetry. A lot of interest has focused on the valley degrees of freedom that can be used to encode binary information. By performing ab initio time-dependent density functional simulation on MoS2, here we show that the spin is not only locked to the valley momenta but strongly coupled to the optical E '' phonon that lifts the lattice mirror symmetry. Once the phonon is pumped so as to break time-reversal symmetry, the resulting Floquet spectra of the phonon-dressed spins carry a net out-of-plane magnetization (approximate to 0.024 mu(B) for single-phonon quantum) even though the original system is non-magnetic. This dichroic magnetic response of the valley states is general for all 2H semiconducting transition-metal dichalcogenides and can be probed and controlled by infrared coherent laser excitation

Acetone Sensing Properties of Nanostructured Copper Oxide Films on Glass Substrate

Access full text - https://doi.org/10.1007/978-3-030-31866-6_56Copper oxide nanostructured films were synthesized via a chemical synthesis (SCS) method and annealed in low vacuum. The morphological properties were investigated using scanning electron microscopy (SEM). The elaborated sensor structures based on CuO/Cu2O films were tested to 100 ppm of acetone vapor. It was observed that by applying different temperatures for rapid thermal annealing the surface morphology of the films can be modified, as well as the composition of the films, which leads to the changes in gas response value for the tested gases. The possibility of controlling the sensitivity of the sensors by changing the RTA treatment temperature and the operating temperature was demonstrated

Controlling the Stability and the Electronic Structure of Transition Metal Dichalcogenide Single Layer under Chemical Doping

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Tuning the Magnetic and Electronic Properties of Monolayer Chromium Tritelluride through Strain Engineering

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Dependence of hole effective mass on nitrogen concentration in W-type strained InAs(N)/GaSb/InAs(N) quantum well lasers

We have investigated the effects of nitrogen N concentration on the properties of hole subbands and effective mass in dilute-nitride type-II InAsN/GaSb laser diodes on InAs substrate with “W” design. Using a 5-bands k·p model, we obtained interesting numerical results for the heavy-hole (hh) and the light-hole (lh) subbands. The hole effective masses were found to be very sensitive to the nitrogen concentration and to the differences in the Luttinger parameters between the well and the barrier. In addition, the hole effective masses are found to be strongly affected by band-anticrossing (BAC) model