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Quantum computing

Jan 14, 2016

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Quantum computing. Motivation. Two approaches to increase efficiency: Nanotechnologies Quantum computers Take advantage of quantum effects and design quantum algorithms. Reversibility. Content. Qubits Multiple qubits Computational basis Quantum gates Bell states circuit - PowerPoint PPT Presentation
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Page 1: Quantum  computing

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Page 2: Quantum  computing

Two approaches to increase efficiency:◦ Nanotechnologies◦ Quantum computers

Take advantage of quantum effects and design quantum algorithms.

Reversibility

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Page 3: Quantum  computing

1. Qubits2. Multiple qubits3. Computational basis4. Quantum gates5. Bell states circuit6. Teleportation circuit

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Page 4: Quantum  computing

The equivalent to a classical bit Can be in the states or as classical bits But also in a superposition state

Possibility of representing different numbers at the same time with only one qubit

But measurement put it back in the state or with probabilities and

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Page 5: Quantum  computing

4 computational basis states for a 2 qubit system

Superposition state

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Page 6: Quantum  computing

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Page 7: Quantum  computing

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Page 8: Quantum  computing

After measurement becomes or

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Page 9: Quantum  computing

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Page 10: Quantum  computing

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Page 11: Quantum  computing

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Page 12: Quantum  computing

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Page 13: Quantum  computing

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Page 14: Quantum  computing

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Page 15: Quantum  computing

M.A. Nielsen & I.L. Chuang, Quantum Computation and Quantum Information, Cambridge University Press, 2000.

P. Kaye, R. Laflamme & M. Mosca, An Introduction to Quantum Computing, Oxford University Press, 2007.

M. Nakahara & T. Ohmi, Quantum Computing: from Linear Algebra to Physical Realizations, CRC Press, 2008.

T. Hey, Quantum Computing: an introduction, Computing & Control Engineering Journal, vol. 10, n°3, 105-112, 1999.

A. Barenco & al., Elementary gates for quantum computation, Phys. Rev., A52, 3457-3467, 1995.

D. Deutsch, R. Jozsa, Rapid Solution of Problems by Quantum Computation, Proceedings: Mathematical and Physical sciences, vol. 439, n°1907, 553-558, 1992.

P. Shor, Algorithms for Quantum Computation: Discrete Logarithms and Factoring, Proceedings: 35th Annual Symposium on Fundamentals of Comp. Science (FOCS), 124-134, 1994.

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