Download presentation

Presentation is loading. Please wait.

Published bySydney Marchman Modified over 3 years ago

1
Mark Tame QTeQ - Quantum Technology at Queen’s Queen’s University, Belfast Fault-tolerant one-way quantum computation using minimal resources - Decoherence-free subspaces (DFS)

2
2/14 Noise in the one-way model for quantum computation Environment effects during time evolution – Decoherence Pauli error General error Loss Local/Global noise: Pauli error General error Loss Preparation of |+> controlled phase gate error controlled unitary gate error Loss from non-deterministic gates Application of CZ ’s Measurement process error in measurement of qubits propagates into the remaining cluster

3
3/14 Work on Fault-tolerance in the one-way model -Raussendorf, PhD Thesis (2003) (http://edoc.ub.unimuenchen.de/archive/00001367) -Nielsen and Dawson, PRA 71, 042323 (2005) -Aliferis and Leung, PRA 73, 032308 (2006) Proved that an Error Threshold existed, which could be determined by mapping noise in the cluster state to noise in a corresponding circuit model. -Dawson, Haselgrove and Nielsen, PRL 96, 020501 (2006) PRA 73, 052306 (2006) Error correcting schemes and associated error threshold values for optical setups STEANE 7 qubit and GOLAY 23 qubit codes -Ralph, Hayes and Gilchrist PRL, 95, 100501 (2005) -Varnava, Browne and Rudolph PRL 97, 120501 (2006) Loss tolerant schemes for linear optics setups -Raussendorf, Harrington and Goyal, Ann. Phys. 321, 2242 (2006) -Raussendorf and Harrington, quant-ph/0610082 (2006) Fault-tolerant using topological error correction and surface codes -Silva et al., quant-ph/0611273 (2006) -Fujii and Yamamoto, quant-ph/0611160 (2006) Most Recently: -Dawson, Haselgrove and Nielsen, PRL 96, 020501 (2006). -Silva et al., quant-ph/0611273 (2006).

4
4/14 Problems with Fault-tolerant schemes in the one-way model Large resource overheads: - A minimum of 7 qubits for an encoded qubit (STEANE code) Complicated structure for the encoded qubit: - Underlying graph to encode qubit is complex Error syndrome extraction techniques add additional overheads “One-buffered”, “two-at-a-time” and “fully-parallel” approaches complicate the model: - They modify the measurement patterns and entangling steps Off-line preparation of ancilla qubits can also be a cumbersome process: - setup dependent Q: Is there a way to achieve fault-tolerence using less resources?

5
5/14 Minimal-resource Fault-tolerance in the one-way model Local Collective noise 4-qubit collective noise 2-qubit collective noise 3-qubit collective noise Universal resource for one-way QC -Van den Nest et al., PRL 97, 150504 (2006)

6
6/14 Decoherence-free subspace one-way model - Simple protection from collective noise G. M. Palma et al., Proc. Roy. Soc. London A 452, 567-584 (1996) Basic 1-bit teleportation unit: 4 physical qubits

7
7/14 Decoherence-free subspace one-way model - Protection from all types of collective noise (I) Theory: Kempe et al., PRA 63 042307 (2001) Experiment: Bourenanne et al., PRL 92 107901 (2004)

8
8/14 Decoherence-free subspace one-way model - Protection from all types of collective noise (II) Knill, Laflamme and Viola PRL 84, 2525 (2000) (Decoherence-free subsystems) Basic 1-bit teleportation unit: 6 physical qubits

9
9/14 Performance of Decoherence-free subspace one-way model - Theoretical (I) M. S. Tame, M. Paternostro, M. S. Kim -submitted (2007) Probe states: QPT techniques: H H H H

10
10/14 Performance of Decoherence-free subspace one-way model - Theoretical (I)

11
11/14 Performance of Decoherence-free subspace one-way model - Experimental (II) R. Prevedel, M. S. Tame, A. Stefanov, M. Paternostro, M. S. Kim and A. Zeilinger -submitted (2007) Standard DFS encoded Information transfer protocol: 4 physical qubits Linear optical setup See also: Kwiat et al., Science 290, 498-501 (2000) for single qubit DFS encoding.

12
12/14 Summary and Outlook M. S. Tame et al., work in progress (2007) 1) Investigating the error threshold performance for asymmetries in the collective approximation How does the performance of the 2- and 3-qubit Codes with asymmetries compare to standard cluster state Quantum Error Correcting Codes (QECC) and the natural fault-tolerance of cluster states? 2) Most resourceful method for the 3-qubit code

13
13/14 Special thanks to Collaborators Queen’s, UK : Mauro Paternostro and Myungshik Kim Vienna, Austria : Robert Prevedel, André Stefanov, Pascal Böhi, Anton Zeilinger Leeds, UK : Vlatko Vedral QUINFO @ London, UK : Chris Hadley, Sougato Bose Palermo, Italy : Massimo Palma

14
14/14 References DFS one-way QC -Hein et al., Proceedings of the International School of Physics "Enrico Fermi" on "Quantum Computers, Algorithms and Chaos", Varenna, Italy, July, 2005; also at quant-ph/0602096 -Raussendorf, Browne and Briegel, PRA 68, 022312 (2003). -Dawson, Haselgrove and Nielsen, PRL 96, 020501 (2006) PRA 73, 052306 (2006) -Lidar and Birgitta Whaley, "Irreversible Quantum Dynamics", F. Benatti and R. Floreanini (Eds.), pp. 83-120 (Springer Lecture Notes in Physics vol. 622, Berlin, 2003); also at quant-ph/0301032 Introduction to graph states and one-way QC using cluster states Fault-tolerant one-way QC using QECC Introduction to DFS -M. S. Tame, M. Paternostro, M. S. Kim -submitted (2007) -R. Prevedel, M. S. Tame, A. Stefanov, M. Paternostro, M. S. Kim and A. Zeilinger -submitted (2007)

20
t=0.15 t=0.5 t=1 t=5

Similar presentations

OK

Quantum Walks, Quantum Gates, and Quantum Computers Andrew Hines P.C.E. Stamp [Palm Beach, Gold Coast, Australia]

Quantum Walks, Quantum Gates, and Quantum Computers Andrew Hines P.C.E. Stamp [Palm Beach, Gold Coast, Australia]

© 2018 SlidePlayer.com Inc.

All rights reserved.

Ads by Google

Ppt on cash flow statement Ppt on astronomy and astrophysics videos Ppt on atm machine working Ppt on regional transport office chennai Ppt on pi in maths what is the product Ppt on networking related topics about psychology Ppt on classical economics states Ppt on teachers day quote Ppt on real numbers for class 9th physics Projector view ppt on ipad