Broadband optical radiation detector

A method and apparatus for detecting optical radiation by optically monitoring temperature changes in a microvolume caused by absorption of the optical radiation to be detected is described. More specifically, a thermal lens forming material is provided which has first and second opposite, substantially parallel surfaces. A reflective coating is formed on the first surface, and a radiation absorbing coating is formed on the reflective coating. Chopped, incoming optical radiation to be detected is directed to irradiate a small portion of the radiation absorbing coating. Heat generated in this small area is conducted to the lens forming material through the reflective coating, thereby raising the temperature of a small portion of the lens forming material and causing a thermal lens to be formed therein

Double-beam optical method and apparatus for measuring thermal diffusivity and other molecular dynamic processes in utilizing the transient thermal lens effect

A sample material was irradiated by relatively high power, short pulses from a dye laser. Energy from the pulses was absorbed by the sample material, thereby forming a thermal lens in the area of absorption. The pulse repetition rate was chosen so that the thermal lens is substantially dissipated by the time the next pulse reaches the sample material. A probe light beam, which in a specific embodiment is a relatively low power, continuous wave (cw) laser beam, irradiated the thermal lens formed in the sample material. The intensity characteristics of the probe light beam subsequent to irradiation of the thermal lens is related to changes in the refractive index of the sample material as the thermal lens is formed and dissipated

Signature of strong atom-cavity interaction on critical coupling

We study a critically coupled cavity doped with resonant atoms with metamaterial slabs as mirrors. We show how resonant atom-cavity interaction can lead to a splitting of the critical coupling dip. The results are explained in terms of the frequency and lifetime splitting of the coupled system.Comment: 8 pages, 5 figure

Formation of iron nitride thin films with Al and Ti additives

In this work we investigate the process of iron nitride (Fe-N) phase formation using 2 at.% Al or 2 at.% Ti as additives. The samples were prepared with a magnetron sputtering technique using different amount of nitrogen during the deposition process. The nitrogen partial pressure (\pn) was varied between 0-50% (rest Argon) and the targets of pure Fe, [Fe+Ti] and [Fe+Al] were sputtered. The addition of small amount of Ti or Al results in improved soft-magnetic properties when sputtered using \pn $\leq$ 10\p. When \pn is increased to 50\p non-magnetic Fe-N phases are formed. We found that iron mononitride (FeN) phases (N at% $\sim$50) are formed with Al or Ti addition at \pn =50% whereas in absence of such addition \eFeN phases (N\pat$\sim$30) are formed. It was found that the overall nitrogen content can be increased significantly with Al or Ti additions. On the basis of obtained result we propose a mechanism describing formation of Fe-N phases Al and Ti additives.Comment: 9 Pages, 7 Figure

Heavy Quarkonium Potential Model and the 1P1{}^1P_1 State of Charmonium

A theoretical explanation of the observed splittings among the P~states of charmonium is given with the use of a nonsingular potential model for heavy quarkonia. We also show that the recently observed mass difference between the center of gravity of the ${}^3P_J$ states and the ${}^1P_1$ state of $c\bar{c}$ does not provide a direct test of the color hyperfine interaction in heavy quarkonia. Our theoretical value for the mass of the ${}^1P_1$ state is in agreement with the experimental result, and its E1 transition width is 341.8~keV. The mass of the $\eta_c'$ state is predicted to be 3622.3~MeV.Comment: 15 page REVTEX documen

Resonance State Wave Functions of 15^{15}Be using Supersymmetric Quantum Mechanics

The theoretical procedure of supersymmetric quantum mechanics is adopted to generate the resonance state wave functions of the unbound nucleus $^{15}$Be. In this framework, we used a density dependent M3Y microscopic potential and arrived at the energy and width of the 1.8 MeV (5/2$^+$) resonance state. We did not find any other nearby resonances for $^{15}$Be. It becomes apparent that the present framework is a powerful tool to theoretically complement the increasingly important accelerator based experiments with unbound nuclei.Comment: 5 pages, 4 figures, Phys. Lett. B (2017

Atypical presentation of visceral leishmaniasis from non-endemic region

A case of atypical and acute presentation of visceral leishmaniasis from non-endemic region, characterised by exudative pleural effusion and hepatitis is reporte