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This paper presents novel power-efficient designs of quaternary logic gates like Quaternary Minimum (QMIN) and Quaternary Maximum (QMAX), Standard Quaternary Inverter (SQI), Standard Quaternary NAND (SQNAND), Standard Quaternary NOR (SQNOR) and Standard Quaternary XOR (SQXOR) using Carbon Nanotube Field Effect Transistor (CNTFET). The designs are based on Pass Transistor Logic (PTL) and use only three types of Carbon Nanotube (CNT) diameters 0.626 nm, 1.018 nm, and 2.27 nm, which lead to lower fabrication costs and enhanced manufacturability when compared to the state-of-the-art designs. The designs are simulated in HSPICE with a 32 nm CNTFET model provided by Stanford University, and the average power and maximum propagation delay obtained from the simulation results are compared with other existing designs. It shows that the proposed designs require 75% to 90% less power and they achieve 73% to 91% less Power Delay Product (PDP) than the latest designs. [ABSTRACT FROM AUTHOR]

In this paper, we report the comparative study of some parameters of II–VI ternary alloy ZnCdTe and II–VI–O dilute oxide ZnCdTeO. The purpose of this comparative study is to establish both the ternary and quaternary alloys as superior materials for optoelectronic and solar cell applications in which the quaternary materials show more superiority than the ternary material. In this purpose, we take the data from the experiments previously done and published in renowned journals and books. The parameters of these alloys are mainly being calculated using Vegard's law and interpolation method of those collected data. It was certainly demonstrated that the incorporation of O atoms produces a high bandgap (Δ E g ) reduction in host ZnCdTe (Zn 1 − x CdxTe) in comparison to the bandgap reduction in host ZnTe material with Cd incorporation. The bandgap of ZnCdTeO (Zn 1 − x CdxTe 1 − y Oy) was found to be reduced to 1.1357 at x = y = 0. 5 and the spin–orbit splitting energy ( Δ SO ) value of ZnCdTeO was calculated to be 1.175 eV for Cd concentration of 0.5 mole and O concentration of 0.1 mole both of which showed excellent results with the prospect of optoelectronic and solar cell applications. The constant rise in the spin–orbit curve signifies a very less internal carrier recombination which decreases the leakage current and augments the efficiency of solar cell. The lattice constants and strain calculation values give very good results and confirm the stability of the materials. Besides, the calculated band offsets values show that for ZnCdTeO, there is higher bandgap reduction than that of ZnCdTe. Moreover, ZnCdTeO covers a wide range of wavelength in the visible region starting from violet region at 393 nm upto red region at 601 nm. Both ZnCdTe and ZnCdTeO are found to have excellent applications in optoelectronic and solar cell devices though quaternary ZnCdTeO proves much supremacy over ternary ZnCdTe in all aspects of the properties. [ABSTRACT FROM AUTHOR]