Solid State Physics Laboratory

About: Solid State Physics Laboratory is a facility organization based out in Delhi, India. It is known for research contribution in the topics: Quantum dot & Dielectric. The organization has 1754 authors who have published 2597 publications receiving 50601 citations.

Optimal selection of SAW sensors for E-Nose applications

Abstract: Electronic noses (E-Nose) are devices used to substitute human or canine olfactory systems in detecting gases or chemical substances. The success of an E-Nose in detecting a set of target gases depends on how optimal is the choice of the gas sensors. This paper proposes a novel algorithm for selection of an optimal set of surface acoustic wave (SAW) sensors for an E-Nose from a given set of available gas sensors. The sensor performance is quantified in terms of separability of data obtained from them. A similarity measure specifying how similar the responses of sensors are when exposed to a set of gases, is also defined. The sensor selection algorithm is then specified as an optimization problem in terms of separability of target gases and similarity of sensor responses. The advantage of the proposed method lies in its performance being independent of the choice of the pattern recognition engine.

Electron-ion correlation in liquid metals from first principles: Liquid Mg and liquid Bi.

Abstract: We present a theoretical determination of electron-ion pair correlation functions ${g}_{\mathrm{ie}}$ in liquid Mg and liquid Bi, two systems with widely different electronic and cohesive properties. Our calculations are based on first-principles molecular-dynamics simulations, which provide an accurate and mutually consistent description of the atomic and electronic structures of these systems. Our results show that ${g}_{\mathrm{ie}}$ exhibits substantially different features in Mg and Bi liquids. For liquid Mg, ${g}_{\mathrm{ie}}$ clearly reflects the delocalization of the valence atomic charge related to metallic bond formation. In the case of Bi, instead, the spherical average implicit in ${g}_{\mathrm{ie}}$ does not allow it to reveal the existence of transient directional bonds which are an important feature of the charge density in this liquid.