Open Access Original Research Article

Characterisation of Defects Induced by Ion-implantation Processing of P+N Shallow Junction Devices

D. Dube, I. Hapazari, J. Zvidzayi

Physical Science International Journal, Page 1-8
DOI: 10.9734/PSIJ/2016/24297

The DLTS technique was used to characterise defects induced by ion-implantation processing in P+N shallow junction devices. BF2 implantation was carried out on silicon diodes pre-armophized by Ge at different energies. The variation of implantation energy and its effects on the type of defects generated and concentration of those defects across the devices were evaluated. From an electronic point of view, defects were categorised into two groups – that is shallow level and deep level defects. The results revealed that the higher the implant energy the more defects, of both types, generated in the device. Effectively, concentrations of both shallow and deep level defects in the devices increased as implant energy increased from 30 to 150 keV. The results also reveal that for low implant energy (30 keV) the defects are mainly the shallow level type and defectconcentration decreases with depth below junction. High energies (60 and 150 keV) show constant defect concentration across the sample thickness or depth.

 

Open Access Original Research Article

Reduction of Environmental Impact of Fixed Bed Nuclear Reactor (FBNR) Waste

Farhang Sefidvash, Ehsan Amozegar, Sumer Sahin, Do Thi Nguyet Minh, Ha Van Thong

Physical Science International Journal, Page 1-9
DOI: 10.9734/PSIJ/2016/25287

The Fix Bed Nuclear Reactor (FBNR) is a pressurized water reactor but its fuel elements are made of Tristructural-Isotropic (TRISO) type particles. Its spent fuel elements may be used as a source of radiation for irradiation purposes in medicine, industry and agriculture. Thereafter, the waste treatment problem is the same as for the fourth generation high-temperature nuclear reactors using TRISO particles. It is found that using the proposed simplified TRISO particles increases the reactivity of the reactor, resulting in higher fuel burnup; while in recycling of its spent fuel, the amount of radioactive carbon is reduced by 57%.

 

Open Access Original Research Article

The Four Aspects of Matter and Radiation

Luίs Dias Ferreira

Physical Science International Journal, Page 1-32
DOI: 10.9734/PSIJ/2016/25894

The idea is advocated here that there are four possible ‘aspects’ for matter to manifest in whatever reference frame because Special Relativity admits four variations to standard Lorentz transformations: two basic variations, bradyonic and pseudotachyonic transformations, applying to respectively subluminal and superluminal reference frames; and two others, derived from these ones by simply reversing time. Pseudotachyonic Relativity (PtR), proposed eight years ago, show that even though one cannot directly detect particles moving faster-than-light, one can detect their co-particles, their ‘images’ moving slower-than-light but with opposite energy, mass and charge; in the process, negative energies naturally arise in Special Relativity, which is quite relevant in field theory. One also concludes that time flows in two opposite senses in the Universe and this is why classic theories are essentially time-reversible. The news here come from the discussion of Dirac equation for the electron and how negative energy turns into positive; one discovers that this equation applies as well to negative mass and finally that its positive and negative solutions are related by ‘antibradyonic’ Lorentz transformation. Generally, in terms of Relativity, this explains why each particle has its own antiparticle. And not just that. In fact, Dirac equation agrees with the proposed Quadrivalent Special Relativity in the conclusion that each particle, in a wide sense, may appear (or manifest itself) in one of four aspects, four versions of a single root – its ‘archeparticle’ –, depending on its mass-energy signature: ‘straight’ particle; antiparticle (with negative-energy): PtR co-particle (also with negative-energy); and co-antiparticle. This conclusion also applies to massless particles, such as photons, with an equivalent alignment-energy signature.

Open Access Original Research Article

Composition Dependent Structural and Optical Properties of Nanocrystallites ZnxCd1-xS

Kamal Bera, Satyajit Saha, Chandan Rana, Paresh Chandra Jana

Physical Science International Journal, Page 1-6
DOI: 10.9734/PSIJ/2016/25796

In this work a novel chemical reduction method at room temperature is described to synthesize nanocrystalline ZnS, CdS, ZnxCd1-xS. The method is cheap and cost effective. The grown nanoparticles are characterized by XRD, TEM, EDX, UV-VIS absorption and PL study. CdS formation is supported by the systematic splitting of x-ray diffraction peak at lower angle and the peaks are identified. ZnS peaks are also identified comparing with ICDD data. EDX analysis shows two other phases Zn 0.8 Cd 0.2 S, Zn 0.5 Cd 0.5 S. The particle sizes are in the range 4-8 nm. The band gap changes with change of composition. Also at each composition the band gap is greater compared to bulk band gap. This indicates quantum confinement takes place. The band gap energy of nanoparticles can be tuned to a lower energy by increasing the Cd content, indicating the formation of the alloyed nanoparticles. PL peak shifts towards higher wavelength as Cd content increases. The peak corresponds to transition associated with surface state.

 

Open Access Original Research Article

Fermi Problem and Superluminal Signals in Quantum Electrodynamics

B. A. Veklenko

Physical Science International Journal, Page 1-12
DOI: 10.9734/PSIJ/2016/26143

Using as an example the Fermi problem dealing with nonstationary transformation of optical excitation from one atom to another the reason of superluminal signals appearance in quantum electrodynamics is clearing. It is shown that the calculation using the conventional methods in Heisenberg and Schrödinger representations in nonstationary problems lead to different results. The Schrödinger representation predicts the existents of specified quantum superluminal signals. In Heisenberg representation the superluminal signals are absent. The reason of non-identity of representations is close connected with using of the adiabatic hypothesis.

 

Open Access Original Research Article

Geodetic Precession under the Paradigm of a Cosmic Membrane

Stefan Von Weber, Alexander Von Eye

Physical Science International Journal, Page 1-14
DOI: 10.9734/PSIJ/2016/26365

Cosmic membrane theory (CM) uses the model of a 4-dimensional balloon with a thin skin, expanding in hyperspace. A homogeneous vector field acts perpendicularly from outside on the membrane and causes the gravitation. CM denies the frame-dragging effect of the spin axis of an orbiting gyroscope (also named Lense-Thirring effect). The results of the Gravity Probe B experiment are correct only for geodetic precession. In the case of the frame-dragging effect, data were selected with a particular goal in mind, and only this way they yielded the desired result.