*Corresponding author, e-mail: sabatt@outlook.com Research Article GU J Sci 35(2): 586-604 (2022) DOI: 10.35378/gujs.797571 Gazi University Journal of Science http://dergipark.gov.tr/gujs Quantum dot Cellular Automata based Fault Tolerant Fingerprint Authentication Systems using Reversible Logic Gates Suhaib AHMED 1,* , Syed Farah NAZ 2 , Sparsh SHARMA 3 1 Baba Ghulam Shah Badshah University, Department of Electronics and Communication Engineering, 185234, Rajouri, Jammu and Kashmir, India 2 Indian Institute of Technology, Discipline of Electrical Engineering, 181221, Jammu, Jammu and Kashmir, India 3 Baba Ghulam Shah Badshah University, Department of Computer Science and Engineering Engineering, 185234, Rajouri, Jammu and Kashmir, India Highlights • Fault tolerance analysis of various XOR gates against single cell addition and missing defects. • Highly fault tolerant XOR is used to design four Fingerprint Authentication Systems in QCA. • Energy dissipation analysis of all four FAS designs is presented at different kink energy levels. • The proposed FAS designs are highly area and cost efficient. Article Info Abstract The limits and difficulties looked by CMOS innovation in the nano system has prompted the exploration of other potential advancements which can work with same functionalities anyway with lower power scattering and higher speed. One such technology is Quantum dot Cellular Automata (QCA). In this paper, QCA is explored to design the authentication system. This paper first presents the basic operating principle of a Fingerprint Authentication System (FAS) followed by fault tolerance analysis of four efficient XOR gate designs in the literature. The XOR gate is then used in the proposed four fault tolerant designs of reversible FAS in QCA, which are based on different reversible gates. Based on the evaluation of different performance parameters, it is seen that the proposed FAS designs are cost efficient and achieve improvement up to 59.46% in terms of number of cells, 67.16% improvement in cell area, 67.14% improvement in total area, 66.67% improvement in latency and 90.51% improvement in terms of circuit cost from the existing design Furthermore, the energy dissipation examination of the proposed designs is also additionally introduced. Subsequently, the proposed designs can be effectively used in biometric applications demanding ultra-low power consumption, higher operating speed and minimal area utilization. Received: 20 Sep 2020 Accepted: 15 Apr 2021 Keywords QCA Fault tolerant design Reversible logic Nanoelectronics Biometric system 1. INTRODUCTION The fundamental nanometer-scale physical constraints of complementary metal oxide semiconductor (CMOS) technology are nearing. It causes a slew of short-channel effects and contributes to the deterioration of field-effect transistor characteristics [1-3]. Alternative nanotechnologies, such as the nanowire transistor, quantum-dot cellular automata (QCA), carbon nanotube field-effect transistor, and others, have already been offered solutions to these problems. QCA, first proposed by C. S. Lent in [1], has been identified as the most recent powerless technology capable of replacing nanoscale-based transistor- based semiconductor technology. It offers intriguing benefits such as increased device density and greater working switching frequencies (in the range of a few THz) at the nanoscale. Because the energy dissipation during state transition and propagation in QCA is negligible [4-6], there is significantly minimal energy dissipation when compared to CMOS technology. QCA is thoroughly investigated, and many logics are being proposed for diverse purposes, including reversible logic [6-9], arithmetic circuits [4, 5, 10-16], code converters [17-21], sequential circuits [17, 22-25], memories [26-29], and so on.