1 / 20

Quantum Computation With Trapped Ions

Quantum Computation With Trapped Ions. Brian Fields. Overview. Intro to Quantum Computation Trapping Ions Ytterbium as a qubit Quantum Gates Future. What does a Quantum Computer Do?. Shor’s Algorithm Factoring products of prime numbers Deutche Jose Algorithm Quantum Simulation

dallon
Download Presentation

Quantum Computation With Trapped Ions

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. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript


  1. Quantum Computation With Trapped Ions Brian Fields

  2. Overview • Intro to Quantum Computation • Trapping Ions • Ytterbium as a qubit • Quantum Gates • Future Brian Fields

  3. What does a Quantum Computer Do? • Shor’s Algorithm • Factoring products of prime numbers • Deutche Jose Algorithm • Quantum Simulation • Magnetism, Ising model, with more qubits possible particle scattering Brian Fields

  4. What Is a Quantum Computer? Divincenzo’sPostulates • Scalable, well defined Qubits • State initialization • Long Coherence Times compared to Gate Speed • Universal Set of Quantum Gates • Efficient State Read Out Brian Fields

  5. History Mass Spec, Atomic Clocks, systems developed • Penning Trap • RF-Paul Trap • Surface Ion Traps Brian Fields

  6. Brian Fields

  7. In order to confine particles, seek linear restoring force F=-kr, Quadrupolar potential gives linear electric field Unfortunately Earnshaw’s theorem proves it is impossible to confine in all directions at once with static fields alone () add an oscillating RF field , Brian Fields

  8. Matheiu Equation Brian Fields

  9. Brian Fields

  10. Desire a closed cycling transition • Detune Doppler cooling laser red of this transition. • Due to Doppler shifts arising from atoms thermal motion laser appears resonant when atom is moving towards beam and further red detuned when moving away • Loses momentum upon absorption moving towards beam, gains momentum upon spontaneous emission but emission is in random direction averages to zero Doppler Cooling Brian Fields

  11. Ytterbium 171+ Hyperfine State Qubit Long Coherence Times~10s Insensitive external B-Field Cooling Closed (with repump beams) Optical Pumping Min error ~ 10^-6 Detection Typical accuracy ~ 98 % Brian Fields

  12. Sideband Cooling Brian Fields

  13. ()()} Brian Fields

  14. Single Qubit Rotations Brian Fields

  15. Single Qubit Rotations • Two Qubit Entangling Gates • CNOT • CiracZoller • Molmer Sorenson Quantum Gates Brian Fields

  16. The previous Hamiltonian's can be applied to generate the following Single Qubit Rotations Quantum Gates Brian Fields

  17. Cirac-Zoller CNOT • The internal state of a control ion is mapped onto the motion of an ion string • The state of the target ion is flipped conditioned on the motional state of the string • Motion of ion string is mapped back to control ion state Result – Flips T if C is Brian Fields

  18. Possible Pulse Sequence for a CNOT gate Brian Fields

  19. More Qubits • Higher Fidelities, better state detection • Motional Decoherence • Modular Trap arrays for Scaling • Photon Ion Flying Qubitentanglement Future Brian Fields

  20. References • Steven Olmschenk.. “QUANTUM TELEPORTATION BETWEEN DISTANT MATTER QUBITS” Doctoral Thesis. University of Maryland. (2009) • David Hayes. “Remote and Local Entanglement of Ions using Photons and Phonons”. Doctoral Thesis. University of Maryland. (2012) • Johnathan Mizrahi. “ULTRAFAST CONTROL OF SPIN AND MOTION IN TRAPPED IONS”. Doctoral Thesis. University of Maryland. (2013) • Timothy Andrew Manning, “QUANTUM INFORMATION PROCESSING WITH TRAPPED ION CHAINS”. Doctoral Thesis. University of Maryland. (2014) • Chris Monroe, et all. “Large-scale modular quantum-computer architecture with atomic memory and photonic interconnects”. PHYSICAL REVIEW A 89, 022317 (2014) • DiVincenzo, David “The Physical Implementation of Quantum Computation”. ARXIV.arXiv:quant-ph/0002077v3 13 Apr 2000 (2008) • J I Cirac, P. Zoller. “Quantum Computations with Cold Trapped Ions”. Physics Review Letters. Volume 74 . Issue 20. May 15 (1994) • H. H¨affner, C. F. Roos, R. Blatt, “Quantum computing with trapped ions”. ARXIV.arXiv:0809.4368v1 [quant-ph] 25 Sep 2008 (2008) Brian Fields

More Related