Mark tame qteq quantum technology at queen s queen s university belfast www qteq info
This presentation is the property of its rightful owner.
Sponsored Links
1 / 26

Mark Tame QTeQ - Quantum Technology at Queen’s Queen’s University, Belfast qteq PowerPoint PPT Presentation


  • 58 Views
  • Uploaded on
  • Presentation posted in: General

Measurement-based quantum protocols with minimal resources. Mark Tame QTeQ - Quantum Technology at Queen’s Queen’s University, Belfast www.qteq.info. Introduction to MB one-way quantum computation Protocols/algorithms on small cluster states Summary and Outlook. Introduction.

Download Presentation

Mark Tame QTeQ - Quantum Technology at Queen’s Queen’s University, Belfast qteq

An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -

Presentation Transcript


Mark tame qteq quantum technology at queen s queen s university belfast www qteq info

Measurement-based quantum protocols with minimal resources

Mark Tame

QTeQ - Quantum Technology at Queen’s

Queen’s University, Belfast

www.qteq.info


Mark tame qteq quantum technology at queen s queen s university belfast qteq

  • Introduction to MB one-way quantum computation

  • Protocols/algorithms on small cluster states

  • Summary and Outlook


Mark tame qteq quantum technology at queen s queen s university belfast qteq

Introduction.

- R. Raussendorf & H.-J. Briegel, PRL 2001- Raussendorf, Browne & Briegel, PRA 2003just type “one-way” or “cluster state” on the arXiv.

Universal resource for one-way QC

-Van den Nest, Miyake, Dür, Briegel

PRL 97, 150504 (2006)


Mark tame qteq quantum technology at queen s queen s university belfast qteq

Introduction.

1) Preparation of |+>

Sac: |0> |0> --> |0> |0>

|0> |1> --> |0> |1>

|1> |0> --> |1> |0>

|1> |1> --> - |1> |1>

| y > = |+> |+> |+> |+>

2) Application of CZ ’s

| y > = 1/4(|+> |+> |+> |+> + |+> |-> |+> |->

+ |-> |+> |-> |+> - |-> |-> |-> |-> )


Mark tame qteq quantum technology at queen s queen s university belfast qteq

Introduction.

- Raussendorf, Browne & Briegel, J. Mod. Opt. 2002


Mark tame qteq quantum technology at queen s queen s university belfast qteq

Introduction.

(i)

| y > = ( a|0> |+> + b|1> |-> )

(ii)

| y > = ( a g |0> |0> + a d |0> |1>+ b g |0> |1> - b d |0> |1> )

(iii)


Mark tame qteq quantum technology at queen s queen s university belfast qteq

Introduction.

1) Preparation of |+>

Local/Global noise:

  • Pauli error

  • General error

  • Loss

2) Application of CZ ’s

  • controlled phase gate error

  • controlled unitary gate error

  • Loss from non-deterministic gates

3) Measurement process

  • error in measurement of qubits

  • propagates into the remaining cluster

4) Environment effects during

time evolution – Decoherence

  • Pauli error

  • General error

  • Loss


Mark tame qteq quantum technology at queen s queen s university belfast qteq

Introduction.

State-of-the-art:

- C.-Y. Lu et al., Nature Physics (2007)

- O. Mandel et al., Nature (2003)


Mark tame qteq quantum technology at queen s queen s university belfast qteq

Protocols.

Some small cluster configurations


Mark tame qteq quantum technology at queen s queen s university belfast qteq

Grover’s Algorithm:

Protocols.

Deutsch’s Algorithm:

M. S. Tame et al., PRL (2007)

P. Walther et al., Nature (2005)

Decoherence-free

subspace processing:

R. Prevedel et al., Nature (2006)

M. S. Tame et al.,

NJP (in press, 2007)

R. Prevedel et al.,

(submitted, 2007)

Quantum Games:

M. Paternostro, M. S. Tame, M. S. Kim, NJP (2005)

R. Prevedel et al., NJP (in press, 2007)


Mark tame qteq quantum technology at queen s queen s university belfast qteq

N. Kiesel et al., PRL (2005)

Protocols.

A.-N. Zhang et al., PRA (R) (2005)

- C.-Y. Lu et al., Nature Physics (2007)

P. Walther et al., Nature (2005);

R. Prevedel et al., Nature (2006); M. S. Tame et al., PRL (2007)


Mark tame qteq quantum technology at queen s queen s university belfast qteq

Protocols.

Grover’s Algorithm:

and active feed-forward!

L .K. Grover, Phys. Rev. Lett. 79, 325 (1997).

R. Prevedel et al., Nature (2006)

P. Walther et al., Nature (2005)


Mark tame qteq quantum technology at queen s queen s university belfast qteq

Protocols.

Deutsch’s Algorithm:

Fair coin:

D. Deutsch, Proc. Roy. Soc. Lond. A 400, 97 (1985).

D. Deutsch and R. Jozsa, Proc. R. Soc. Lond. A 439, 553 (1992).

R. Cleve et al., Proc. R. Soc. Lond. A 454, 399 (1998).

M. S. Tame et al., PRL (2007).

Unfair coin:


Mark tame qteq quantum technology at queen s queen s university belfast qteq

Protocols.

Deutsch’s Algorithm:

M. S. Tame et al., PRL (2007)


Mark tame qteq quantum technology at queen s queen s university belfast qteq

Protocols.

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).

-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

-Silva et al., quant-ph/0611273 (2006).

Fault-tolerant using

topological error

correction and

surface codes

-Raussendorf, Harrington and Goyal, Ann. Phys. 321, 2242 (2006)

-Raussendorf and Harrington, quant-ph/0610082 (2006)

-Silva et al., quant-ph/0611273 (2006)

-Fujii and Yamamoto, quant-ph/0611160 (2006)

Most Recently:


Mark tame qteq quantum technology at queen s queen s university belfast qteq

Protocols.

G. M. Palma et al., Proc. Roy. Soc. London A 452, 567-584 (1996)

Basic 1-bit teleportation unit: 4 physical qubits


Mark tame qteq quantum technology at queen s queen s university belfast qteq

Protocols.

Probe states:

H

H

QPT techniques:

H

H

M. S. Tame, M. Paternostro, M. S. Kim

NJP (in press, 2007)


Mark tame qteq quantum technology at queen s queen s university belfast qteq

Protocols.

Gt=0.5

Gt=0.15

Gt=1

Gt=5

M. S. Tame, M. Paternostro, M. S. Kim

NJP (in press, 2007)


Mark tame qteq quantum technology at queen s queen s university belfast qteq

Protocols.

Linear optical setup

DFS encoded

R. Prevedel, M. S. Tame, A. Stefanov,

M. Paternostro, M. S. Kim and A. Zeilinger

(submitted, 2007)

Information transfer protocol: 4 physical qubits

See also:

Kwiat et al., Science 290, 498-501 (2000)

for single qubit DFS encoding.


Mark tame qteq quantum technology at queen s queen s university belfast qteq

Protocols.

Protection from all collective errors

M. S. Tame, M. Paternostro, M. S. Kim

NJP (in press, 2007)


Mark tame qteq quantum technology at queen s queen s university belfast qteq

Summary.

Grover’s

Algorithm

Active

Feed-forward

Quantum Games

DFS Protocol

Deutsch’s Algorithm


Mark tame qteq quantum technology at queen s queen s university belfast qteq

Polarisation-momentum

entangled cluster states

Outlook.

G. Vallone et al., PRL (2007)

Continuous Variable cluster states

X. Su et al., PRL (2007)

M. S. Tame et al., PRA (2005)

Gross and Eisert., PRL (2007)

K. Chen et al., Arxiv (2007)

Van den Nest, Miyake, Dür, Briegel

PRL 97, 150504 (2006)

and more…

M. S. Tame et al.,

(work in progress, 2007)


Mark tame qteq quantum technology at queen s queen s university belfast qteq

Thanks for listening

Special thanks to Collaborators

: Mauro Paternostro and Myungshik Kim

Queen’s, UK

: Robert Prevedel,

André Stefanov, Pascal Böhi,

Anton Zeilinger

: Vlatko Vedral

Vienna, Austria

Leeds, UK

QUINFO @

: Chris Hadley,

Sougato Bose

: Massimo Palma

London, UK

Palermo, Italy


Mark tame qteq quantum technology at queen s queen s university belfast qteq

Protocols.

Quantum Games:

J. Eisert, M. Wilkens, M. Lewenstein, PRL (1999)

M. Paternostro, M. S. Tame, M. S. Kim, NJP (2005)

R. Prevedel et al., NJP (in press, 2007)

Rational reasoning causes each player to pick

this strategy.

Dominant Strategy: A strategy that does at least as well

as any competing strategy against any

possible moves by the other players.


Mark tame qteq quantum technology at queen s queen s university belfast qteq

Pareto Optimal: The set of strategies from

which no player can obtain a higher

pay-off, without reducing the pay-off of another.

Protocols.

Quantum Games:

J. Eisert, M. Wilkens, M. Lewenstein, PRL (1999)

M. Paternostro, M. S. Tame, M. S. Kim, NJP (2005)

R. Prevedel et al., NJP (in press, 2007)

Find by elimination

Nash Equilibrium: The set of strategies where no player can benefit by changing

their strategy, while the other players keep their strategy

unchanged.


Mark tame qteq quantum technology at queen s queen s university belfast qteq

Protocols.

Quantum Games:

J. Eisert, M. Wilkens, M. Lewenstein, PRL (1999)

M. Paternostro, M. S. Tame, M. S. Kim, NJP (2005)

R. Prevedel et al., NJP (in press, 2007)

Pareto Optimal / Nash Equilibrium

(3,3) Payoff


  • Login