Journal of Innovative Research and Development Vol.-1, Issue-2, 2016, pp.36-42 Copyright©2016, JIRD Page | 36 Research Article DESIGN OF ULTRA LOW POWER LOOK UP TABLE USING QUANTUM DOT CELLULAR AUTOMATA FOR NANO SCALE COMMUNICATION Dheeraj Sharma, Narender Kumar Natraj Polytechnic College, India Abstract Quantum Dot cellular Automata is quite promising alternative to CMOS devices that performs its operation using electronic charge of a cell. The circuit based on Quantum dot automata has various advantage like very high speed, low power consumption, high integrity and high parallel processing. In this paper we focused on designing of LUT (Look Up Table) which is based on Quantum dot cellular automata technology. LUT consist of three component these are 4 to 16 decoder circuit, a 16 bit memory and a output circuit. In this paper we implemented these three component in QCA designer tool and also perform simulation for LUT. Keywords: QCA,LUT,Decoder,Memory,Output Circuit,CMOS. 1. Introduction In present scenario the demand of application on chip is increasing day by day. Due to this the size of chip also increases. To overcome this problem and provide fast and very small chip, the quantum dot cellular automata is best alternative. Advancement in the microelectronic industry depends upon the size of the device. At the length of gate below 0.1μm FET will start to encounter fundamental effects that make it difficult to further scaling. The best way for microelectronic industries to maintain the size of device density is to change FET based devices to nanostructures based devices. The advantage of quantum dot cellular automata are very high packaging density due to small size of quantum dot, extremely low power and very simple interconnection.[1]. 2. QCA Background A basic QCA consist of four quantum dots in square array. In this the electron are able to tunnel the through the dots but cannot leave the cell. If two electrons are present in the cell then coulomb repulsion will force them towards the corner of the cell. There are two types of polarization as shown in Fig.1 that are logic ‘0’ and logic ‘1’[2]. The coulomb interaction between the electrons will cause the cell in same polarization. If the polarization of one cell will change then the second cell exhibits a highly bistable switching of its state of polarization. The simple example of QCA is array of cell as shown in Fig. 2. Because the cells are coupled capacitively to their neighbour cell so the polarization of ground of all cell are same [3]. In this state electrons are spaced widely as possible, providing lowest energy. Figure 1 QCA cell polarization for logic “0” or P=-1