Journal of Nanoparticle Research

, Volume 3, Issue 1, pp 27–37 | Cite as

New Design for Quantum Dots Cellular Automata to obtain Fault Tolerant Logic Gates

  • Amir Fijany
  • Benny N. Toomarian


In this paper, we analyze fault tolerance properties of the Majority Gate, as the main logic gate for implementation with Quantum dots Cellular Automata (QCA), in terms of fabrication defect. Our results demonstrate the poor fault tolerance properties of the conventional design of Majority Gate and thus the difficulty in its practical application. We propose a new approach to the design of QCA-based Majority Gate by considering two-dimensional arrays of QCA cells rather than a single cell for the design of such a gate. We analyze fault tolerance properties of such Block Majority Gates in terms of inputs misalignment and irregularity and defect (missing cells) in assembly of the array. We present simulation results based on semiconductor implementation of QCA with an intermediate dimensional dot of about 5 nm in size as opposed to magnetic dots of greater than 100 nm or molecular dots of 2–5Å. Our results clearly demonstrate the superior fault tolerance properties of the Block Majority Gate and its greater potential for a practical realization. We also show the possibility of designing fault tolerant QCA circuits by using Block Majority Gates.

Quantum dots based computing Quantum dots Cellular Automata quantum dots logic gates fault tolerant logic gates Majority Gate 


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.


  1. Amlani, I., A.O. Orlov, G.H. Bernstein, C.S. Lent & G.L. Snider, 1997. Realization of a functional cell for quantum-dot cellular automata. Science 277, 289.Google Scholar
  2. Amlani, I., A.O. Orlov, G. Toth, C.S. Lent, G.H. Bernstein & G.L. Snider, 1999. Digital logic gate using quantum-dot cellular automata. Applied Physics Lett.74, 2875.Google Scholar
  3. Ashoori, R.C., H.L. Stormer, J.S. Weiner, L.N. Pfeiffer, K.W. Baldwin & W.West, 1993. N-electron ground state energies of a quantum dot in a magnetic field. Phys. Rev. Lett. 71, 613.Google Scholar
  4. Cowburn, R. P. & M. E. Welland, 2000. Room temperature magnetic quantum cellular automata. Science 287, 1466.Google Scholar
  5. Fijany, A., B.N. Toomarian & M. Spotnitz, 1999. Novel highly parallel architectures using quantum dot-based hardware. Proc. Parallel Computing 99 (PARCO 99), Delft, The Netherland.Google Scholar
  6. Fijany, A., B.N. Toomarian, K. Modarress & M. Spotnitz, 2001. Quantum dots-based hardware architecture for implementation of a bit-serial adder. To appear in NASA J. Tech Brief.Google Scholar
  7. Fijany, A., B.N. Toomarian & K. Modarress, 2001. Quantum dots cellular automata fault tolerant logic gates: block gates with imprecise assembly. To appear in NASA J. Tech Brief.Google Scholar
  8. Gin, A., S. Williams, H. Meng & P.D. Tougaw, 1999. Hierarchical design of quantum-dot cellular automata devices. J. Applied Physics 85, 3713.Google Scholar
  9. Kogge, P., 1999. Personal Communications.Google Scholar
  10. Lent, C.S. & P.D. Tougaw, 1993. Line of interacting quantum-dot cells: a binary wire. J. Applied Physics. 74, 6227.Google Scholar
  11. Lent, C.S., P.D. Tougaw & W. Prod, 1994. Quantum cellular automata: The physics of computing with quantum dot molecules. PhysComp 94: Proc.Workshop Phys. Comp., IEEE Computer Society Press.Google Scholar
  12. Lent, C.S. & P.D. Tougaw, 1997. A device architecture for computing with quantum dots. Proc. IEEE 85(4), 541.Google Scholar
  13. Meurer, B., D. Heitmann & Ploog, K., 1992. Single electron charging of quantum-dot atoms. Phys. Rev. Lett. 68, 1371.Google Scholar
  14. Orlov, A.O., I. Amlani, G. Toth, C.S. Lent, G.H. Bernstein & G.L. Snider, 1997. Experimental demonstration of a binary wire for quantum-dot cellular automata. Applied Physics Lett. 74, 928.Google Scholar
  15. Smith, C.G., 1999. Computation without current. Science 284, 274.Google Scholar
  16. Tougaw, P.D. & C.S. Lent. 1994. Logical device implementation using quantum cellular automata. J. Applied Physics, 75, 1818.Google Scholar

Copyright information

© Kluwer Academic Publishers 2001

Authors and Affiliations

  • Amir Fijany
    • 1
  • Benny N. Toomarian
    • 1
  1. 1.Jet Propulsion LaboratoryCalifornia Institute of TechnologyPasadenaUSA

Personalised recommendations