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The M\"ossbauer spectroscopy is presented as an alternative experimental technique to be pursued in the detec-tion of Coherent Elastic{\nu}-Nucleus Scattering (CENNS). The neutrino transferred energy in the neutrino-nucleusinteraction causes a perturbation at the nuclear levels which are responsible for gamma radiation in M\"ossbauerresonance. The main characteristic of M\"ossbauer spectroscopy is the recoil less condition imposed on the nucleiimposed by quantum restrictions of the crystalline array potential. Coherent neutrino scattering is expected tooccurs low energy regime of the beam, typically below 30 MeV, at higher neutrino energies small incoherencecomponent appears in the scattering[30] as disturbances within the internal nuclear degrees of freedom. Inthis work we have shown that using anti neutrino reactor beam, with the accuracy of M\"ossbauer technique itspossible to obtain a measurable signature of the Coherent neutrino Scattering., Comment: 6 Pages, 3 figures

This work describes an experiment and some results from instability involving the proliferation achieved by cells over some radio frequency electromagnetic field. Saccharomyces cerevisiae cells were cultured, and separate samples were examined within 6 hours. The frequency, the pulse width and peak-to-peak voltages were fixed. Producing at least 1 kV across the cell membrane in milk suspension. It was observed that in the presence of the electromagnetic field the cells had their time life drastically reduced when compared to the control sample., Comment: 3 pages, 5 figures

The M\"ossbauer technique is proposed as an alternative experimental procedure to be used in the detection of Coherent Elastic $\nu$-Nucleus Scattering (CENNS). The $Z_{0}$-boson exchange is considered as a perturbation on the nuclear mean-field potential with a change in the valence neutron quantum states in the $^{57}Fe$ nucleus of the M\"ossbauer detector sample. This nuclei is a typical isotope used in M\"ossbauer spectroscopy. Perturbed level of the valence neutron accommodates the transferred energy, modifying the location of the isometric peak of the M\"ossbauer electromagnetic resonance. We calculate the isometric shift correction due CENNS and show that this quantity is able to be detected with enough precision. Therefore, the difference between the M\"ossbauer isometric shift in the presence of a reactor-neutrino beam and without the neutrinos flux is pointed out as a figure of merit to manifest CENNS. In this work, we show that the CENNS correction of the Isomeric Shift is of $\approx 10^{-7}$eV, which is greater than the $10^{-10}$eV resolution of the technique., Comment: 4 pages, 1 figure. Poster presented at the XIV International Workshop on Hadron Physics, Florian\'opolis, Brazil, March 2018

Germanium is a strong candidate as a laser source for silicon photonics. It is widely accepted that the band structure of germanium can be altered by tensile strain so as to reduce the energy difference between its direct and indirect band gaps. However, the conventional deformation potential model most widely adopted to describe this transformation happens to have been investigated only up to 1 % uniaxially loaded strains. In this work, we use a micro-bridge geometry to uniaxially stress germanium along [100] up to $\varepsilon_{100}$=3.3 % longitudinal strain and then perform electro-absorption spectroscopy. We accurately measure the energy gap between the conduction band at the $\Gamma$ point and the light- and heavy-hole valence bands. While the experimental results agree with the conventional linear deformation potential theory up to 2 % strain, a significantly nonlinear behavior is observed at higher strains. We measure the deformation potential of germanium to be a = -9.1 $\pm$ 0.3 eV and b = -2.32 $\pm$ 0.06 eV and introduce a second order deformation potential. The experimental results are found to be well described by tight-binding simulations. These new high strain coefficients will be suitable for the design of future CMOS-compatible lasers and opto-electronic devices based on highly strained germanium.

Ge under high strain is predicted to become a direct bandgap semiconductor. Very large deformations can be introduced using microbridge devices. However, at the microscale, strain values are commonly deduced from Raman spectroscopy using empirical linear models only established up to 1.2% for uniaxial stress. In this work, we calibrate the Raman-strain relation at higher strain using synchrotron based microdiffraction. The Ge microbridges show unprecedented high tensile strain up to 4.9 % corresponding to an unexpected 9.9 cm-1 Raman shift. We demonstrate experimentally and theoretically that the Raman strain relation is not linear and we provide a more accurate expression., Comment: 10 pages, 4 figures

We study the dynamics of a charged spin-1/2 particle in an external 5-dimensional electromagnetic field. We then consider that we are at the $TeV$\ scale, so that we can access the fifth dimension and carry out our physical considerations in a 5-dimensional brane. In this brane, we focus our attention to the quantum-mechanical dynamics of a charged particle minimally coupled to the 5-dimensional electromagnetic field. We propose a way to identify the Abraham-Lorentz back reaction force as an effect of the extra (fifth) dimension. Also, a sort of dark matter behavior can be identified in a particular regime of the dynamics of the particle interacting with the bulk electric field., Comment: 8 pages

In this work, we present two possible venues to accomodate the $K_{F}$-type Lorentz-symmetry violating Electrodynamics in an $N=1$-supersymmetric framework. A chiral and a vector superfield are chosen to describe the background that signals Lorentz-symmetry breaking. In each case, the $\ K_{\mu \nu \kappa \lambda }$-tensor is expressed in terms of the components of the background superfield that we choose to describe the breaking. We also present in detail the actions with all fermionic partners of the background that determine $\ K_{\mu \nu \kappa \lambda }$., Comment: 10 pages

The connection between the supersymmetric quantum mechanics involving two-component eigenfunctions and the stability equation associated with two classical configurations is investigated, and a matrix superpotential is deduced. The issue of stability is ensured for the Bogomol'nyi-Prasad-Sommerfield (BPS) states on two domain walls in a scalar potential model containing up to fourth-order powers in the fields, which is explicit demonstrated using the intertwining operators in terms of 2x2-matrix superpotential in the algebraic framework of supersymmetry in quantum mechanics. Also, a non-BPS state is found to be non-stable via fluctuation hessian matrix., Comment: Revised version. Revtex, 4 figures, 22 pages, to appear in International Journal of Modern Physics, Vol. 21 (2006)

One considers the quantum dynamics of a charged spin-1/2 particle in an extended external eletromagnetic field that arises from the reduction of a 5-dimensional Abelian gauge theory. The non-relativistic regime of the reduced 4D-dynamics is worked out and one identifies the system as a sector of an N=2-supersymmetric quantum-mechanical dynamics. The full supersymmetric model is studied and one checks the algebra of the fermionic charges; the conclusion is that no central charge drops out. The possible r\^ole of the extra external fields, a scalar and a magnetic-like field, is discussed., Comment: 19 pages. Latex format. No figures

We study (1+1)-dimensional turbulence in the framework of the Martin-Siggia-Rose field theory formalism. The analysis is focused on the asymptotic behaviour at the right tail of the probability distribution function (pdf) of velocity differences, where shock waves do not contribute. A BRS-preserving scheme of phase space reduction, based on the smoothness of the relevant velocity fields, leads to an effective theory for a few degrees of freedom. The sum over fluctuations around the instanton solution is written as the expectation value of a functional of the time-dependent physical fields, which evolve according to a set of Langevin equations. A natural regularization of the fluctuation determinant is provided from the fact that the instanton dominates the action for a finite time interval. The transition from the turbulent to the instanton dominated regime is related to logarithmic corrections to the saddle-point action, manifested on their turn as multiplicative power law corrections to the velocity differences pdf., Comment: The revised version contains more detailed discussions on some technical points