who are we l.
Download
Skip this Video
Loading SlideShow in 5 Seconds..
Who are we? PowerPoint Presentation
Download Presentation
Who are we?

Loading in 2 Seconds...

play fullscreen
1 / 15

Who are we? - PowerPoint PPT Presentation


  • 89 Views
  • Uploaded on

Who are we?. Quantum Information Group Department of Physics Technical University of Denmark (DTU). Quantum Information Processing Group Max Planck Institute for the Science of Light Erlangen, Germany. Collaborators: Lodahl et al (DTU Fotonik) Sørensen et al (NBI)

loader
I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
capcha
Download Presentation

PowerPoint Slideshow about 'Who are we?' - elvin


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
who are we

Who are we?

Quantum Information Group

Department of Physics

Technical University of Denmark (DTU)

Quantum Information Processing Group

Max Planck Institute for the Science of Light

Erlangen, Germany

Collaborators:

Lodahl et al (DTU Fotonik)

Sørensen et al (NBI)

Filip et al (Palacky Uni)

Takeoka, Sasaki et al (NICT)

Furusawa et al (Tokyo Uni)

Drummond, Corney (UQ)

We develop technology for

Quantum Computing

Quantum Communication

Quantum Metrology

processing and metrology

Processing and metrology

U.L.A., G. Leuchs and C. Silberhorn, Laser and Photonics Reviews, 4, 337 (2010)

slide3

What is quantum information?

Coding information into a discrete variable:

Lecture by Kumar

2D Examples

Poster by Jain

Lecture by Boyd

PhD talks (Tipsmark, Benichi)

Lectures by Childress

and Imamoglu

Coding information into a continuous variable:

Coherent state:

= Gaussian

Examples

Squeezed state:

= Sqz. Gaussian

Single photon:

= 1st order HG

Lectures by Kippenberg, Hammerer, Polzik and Mølmer

what do we do

Quantum information protocol

  • Quantum averaging (PRA, 82, 021801 (2010) )
  • Quantum erasure correcting code (Nat. Phot. 2010)
  • Quantum Key Distribution
  • Quantum Random number generation (Nat. Phot 2010)
  • Violating Bells inequality with a hybrid detection system
  • Hybrid quantum repeater using cat states (arXiv: 1004.0083)
  • Noiseless Quantum Amplification (Nat. Phys. 2010)
  • Quantum state generation
  • Squeezed state / Entangled state
  • Cat state
  • Single photon state

What do we do?

  • Quantum metrology/estimation
  • Phase measurement
  • Super-resolution with coherent states
  • Binary coherent state discrimination
  • (PRL 104, 100505 (2010))

No code

With code

slide5

Goal

To reduce the phase noise of a coherent state through amplification

slide6

Deterministic amplification

Input-output relation:

Gain = G

Louisell, W.H I. Phys. Rev. 124 1646 (1961); Haus, H.A. andMullen, J.A. Phys. Rev. 128 5 (1962); Caves, C.M. Phys. Rev. D 26 , 8 (1982).

slide7

Probabilistic amplification

Gain = G

Ralph, T.C. and Lund, A.B. QCMC Proc. of 9th Int. Conf. 155-160

Babichev et al. EPL (2003); Xiang et al. Nat. Ph. 4, 316 (2010); Ferreyrol et al. PRL 104, 123603 (2010);

(Zavatta et al. arXiv:1004.3399v1 [quant-ph]; Marek and Filip, PRA 81, 022302 (2010); Fiurasek PRA 80, 053822 2009)

slide8

Probabilistic amplification

N

Marek and Filip, PRA 81,

022302 (2010)

a+M

aM

a+

a

Zavatta et al. arXiv:1004.3399; Fiurasek PRA 80, 053822 (2009)

phase concentration scheme10
Phase-ConcentrationScheme
  • How does it really work?
slide11

Experimental Setup

- homodyne

tomography

- diodelaser (809nm)

- modecleaning

- LO split-off

  • electro-optical
  • modulatorsand a
  • half-waveplate

- tap-off

measurement

- feed-forward

slide12

Wigner functions

|acoh |2 = 0.186

Usuga, Muller, Wittmann, Marek, Filip, Marquardt, Leuchs and Andersen, Nature Physics (2010)

slide13

Phase variance

Usuga, Muller, Wittmann, Marek, Filip, Marquardt, Leuchs and Andersen, Nature Physics (2010)

slide14

Conclusion

Simple Setup

ReducedVariance

slide15

What is quantum information?

Single mode field

Degrees of freedom

Continuous:

Discrete:

Photon number, Polarization, Orbital Angular Momentum