Skip to main content

Thank you for visiting nature.com. You are using a browser version with limited support for CSS. To obtain the best experience, we recommend you use a more up to date browser (or turn off compatibility mode in Internet Explorer). In the meantime, to ensure continued support, we are displaying the site without styles and JavaScript.

Optical control of one and two hole spins in interacting quantum dots

Abstract

A single hole spin in a semiconductor quantum dot has emerged as a quantum bit that is potentially superior to an electron spin. A key feature of holes is that they have a greatly reduced hyperfine interaction with nuclear spins, which is one of the biggest difficulties in working with an electron spin. It is now essential to show that holes are viable for quantum information processing by demonstrating fast quantum gates and scalability. To this end, we have developed InAs/GaAs quantum dots coupled through coherent tunnelling and charged with controlled numbers of holes. We report fast, single-qubit gates using a sequence of short laser pulses. We then take the important next step towards scalability of quantum information by optically controlling two interacting hole spins in separate dots.

Access options

Rent or Buy article

Get time limited or full article access on ReadCube.

from$8.99

All prices are NET prices.

Figure 1: Design of the experiment.
Figure 2: Bias-dependent spectroscopy.
Figure 3: Single hole spin control.
Figure 4: Two weakly interacting hole spins.
Figure 5: Two strongly interacting hole spins.

References

  1. 1

    Englund, D., Faraon, A., Zhang, B., Yamamoto, Y. & Vuckovic, J. Generation and transfer of single photons on a photonic chip. Opt. Express 15, 5550–5558 (2007).

    ADS  Article  Google Scholar 

  2. 2

    Berezovsky, J., Mikkelson, M. H., Stoltz, N. G., Coldren, L. A. & Awschalom, D. D. Picosecond coherent optical manipulation of a single electron spin in a quantum dot. Science 320, 349–352 (2008).

    ADS  Article  Google Scholar 

  3. 3

    Press, D., Ladd, T. D., Zhang, B. & Yamamoto, Y. Complete quantum control of a single quantum dot spin using ultrafast optical pulses. Nature 456, 218–221 (2008).

    ADS  Article  Google Scholar 

  4. 4

    Greilich, A. et al. Ultrafast optical rotations of electron spins in quantum dots. Nature Phys. 5, 262–266 (2009).

    ADS  Article  Google Scholar 

  5. 5

    Kim, E. D. et al. Fast spin rotations by optically controlled geometric phases in a charge-tunable InAs quantum dot. Phys. Rev. Lett. 104, 167401 (2010).

    ADS  Article  Google Scholar 

  6. 6

    Press, D. et al. Ultrafast optical spin echo in a single quantum dot. Nature Photon. 4, 367–370 (2010).

    ADS  Article  Google Scholar 

  7. 7

    de Vasconcellos, S. M., Gordon, S., Bichler, M., Meier, T. & Zrenner, A. Coherent control of a single exciton qubit. Nature Photon. 4, 545–548 (2010).

    ADS  Article  Google Scholar 

  8. 8

    Kim, D., Carter, S. G., Greilich, A., Bracker, A. S. & Gammon, D. Ultrafast optical control of entanglement between two quantum-dot spins. Nature Phys. 7, 223–229 (2011).

    ADS  Article  Google Scholar 

  9. 9

    Heiss, D. et al. Observation of extremely slow hole spin relaxation in self-assembled quantum dots. Phys. Rev. B 76, 241306(R) (2007).

    ADS  Article  Google Scholar 

  10. 10

    Gerardot, B. D. et al. Optical pumping of a single hole spin in a quantum dot. Nature 451, 441–444 (2008).

    ADS  Article  Google Scholar 

  11. 11

    Brunner, D. et al. A coherent single-hole spin in a semiconductor. Science 325, 70–72 (2009).

    ADS  Article  Google Scholar 

  12. 12

    Merkulov, I. A., Efros, A. L. & Rosen, M. Electron spin relaxation by nuclei in semiconductor quantum dots. Phys. Rev. B 65, 205309 (2002).

    ADS  Article  Google Scholar 

  13. 13

    Greilich, A. et al. Mode locking of electron spin coherences in singly charged quantum dots. Science 313, 341–345 (2006).

    ADS  Article  Google Scholar 

  14. 14

    Petta, J. R. et al. Coherent manipulation of coupled electron spins in semiconductor quantum dots. Science 309, 2180–2184 (2005).

    ADS  Article  Google Scholar 

  15. 15

    Fischer, J., Coish, W. A., Bulaev, D. V. & Loss, D. Spin decoherence of a heavy hole coupled to nuclear spins in a quantum dot. Phys. Rev. B 78, 155329 (2008).

    ADS  Article  Google Scholar 

  16. 16

    Fischer, J. & Loss, D. Hybridization and spin decoherence in heavy-hole quantum dots. Phys. Rev. Lett. 105, 266603 (2010).

    ADS  Article  Google Scholar 

  17. 17

    Eble, B. et al. Hole–nuclear spin interaction in quantum dots. Phys. Rev. Lett. 102, 146601 (2009).

    ADS  Article  Google Scholar 

  18. 18

    Fallahi, P., Yilmaz, S. T. & Imamoglu, A. Measurement of a heavy-hole hyperfine interaction in InGaAs quantum dots using resonance fluorescence. Phys. Rev. Lett. 105, 257402 (2010).

    ADS  Article  Google Scholar 

  19. 19

    Chekhovich, E. A., Krysa, A. B., Skolnick, M. S. & Tartakovskii, A. I. Direct measurement of the hole–nuclear spin interaction in single InP/GaInP quantum dots using photoluminescence spectroscopy. Phys. Rev. Lett. 106, 027402 (2011).

    ADS  Article  Google Scholar 

  20. 20

    Winkler, R. Spin–Orbit Coupling Effects in Two-Dimensional Electron and Hole Systems (Springer-Verlag, 2003).

    Book  Google Scholar 

  21. 21

    Bayer, M. et al. Fine structure of neutral and charged excitons in self-assembled In(Ga)As/(Al)GaAs quantum dots. Phys. Rev. B 65, 195315 (2002).

    ADS  Article  Google Scholar 

  22. 22

    Doty, M. F. et al. Electrically tunable g factors in quantum dot molecular spin states. Phys. Rev. Lett. 97, 197202 (2006).

    ADS  Article  Google Scholar 

  23. 23

    Andlauer, T. & Vogl, P. Electrically controllable g tensors in quantum dot molecules. Phys. Rev. B 79, 045307 (2009).

    ADS  Article  Google Scholar 

  24. 24

    Doty, M. F. et al. Antibonding ground states in InAs quantum-dot molecules. Phys. Rev. Lett. 102, 047401 (2009).

    ADS  Article  Google Scholar 

  25. 25

    Kavokin, K. Symmetry of anisotropic exchange interactions in semiconductor nanostructures. Phys. Rev. B 69, 075302 (2004).

    ADS  Article  Google Scholar 

  26. 26

    Scheibner, M., Bracker, A. S., Kim, D. & Gammon, D. Essential concepts in the optical properties of quantum dot molecules. Solid State Commun. 149, 1427–1435 (2009).

    ADS  Article  Google Scholar 

  27. 27

    Stinaff, E. A. et al. Optical signatures of coupled quantum dots. Science 311, 636–639 (2006).

    ADS  Article  Google Scholar 

  28. 28

    Krenner, H. J. et al. Optically probing spin and charge interactions in a tunable artificial molecule. Phys. Rev. Lett. 97, 076403 (2006).

    ADS  Article  Google Scholar 

  29. 29

    Doty, M. F. et al. Optical spectra of doubly charged quantum dot molecules in electric and magnetic fields. Phys. Rev. B 78, 115316 (2008).

    ADS  Article  Google Scholar 

  30. 30

    Atature, M. et al. Quantum-dot spin-state preparation with near-unity fidelity. Science 312, 551–553 (2006).

    ADS  Article  Google Scholar 

  31. 31

    Xu, X. et al. Fast spin state initialization in a singly charged InAs–GaAs quantum dot by optical cooling. Phys. Rev. Lett. 99, 097401 (2007).

    ADS  Article  Google Scholar 

  32. 32

    Kim, D. et al. Optical spin initialization and nondestructive measurement in a quantum dot molecule. Phys. Rev. Lett. 101, 236804 (2008).

    ADS  Article  Google Scholar 

  33. 33

    Vamivakas, A. N. et al. Observation of spin-dependent quantum jumps via quantum dot resonance fluorescence. Nature 467, 297–300 (2010).

    ADS  Article  Google Scholar 

  34. 34

    Ladd, T. D. et al. Pulsed nuclear pumping and spin diffusion in a single charged quantum dot. Phys. Rev. Lett. 105, 107401 (2010).

    ADS  Article  Google Scholar 

  35. 35

    Xu, X. et al. Optically controlled locking of the nuclear field via coherent dark-state spectroscopy. Nature 459, 1105–1109 (2009).

    ADS  Article  Google Scholar 

  36. 36

    Latta, C. et al. Confluence of resonant laser excitation and bidirectional quantum-dot nuclear-spin polarization. Nature Phys. 5, 758–763 (2009).

    ADS  Article  Google Scholar 

  37. 37

    Bracker, A. S. et al. Engineering electron and hole tunneling with asymmetric InAs quantum dot molecules. Appl. Phys. Lett. 89, 233110 (2006).

    ADS  Article  Google Scholar 

  38. 38

    Calarco, T., Datta, A., Fedichev, P., Pazy, E. & Zoller, P. Spin-based all-optical quantum computation with quantum dots: understanding and suppressing decoherence. Phys. Rev. A 68, 012310 (2003).

    ADS  Article  Google Scholar 

  39. 39

    Emary, C. & Sham, L. J. Optically controlled logic gates for two spin qubits in vertically coupled quantum dots. Phys. Rev. B 75, 125317 (2007).

    ADS  Article  Google Scholar 

  40. 40

    Economou, S. E. & Reinecke, T. L. Optically induced spin gates in coupled quantum dots using the electron–hole exchange interaction. Phys. Rev. B 78, 115306 (2008).

    ADS  Article  Google Scholar 

  41. 41

    De Greve, K. et al. Ultrafast coherent control and suppressed nuclear feedback of a single quantum dot hole qubit. Nature Phys. http://dx.doi.org/10.1038/nphys2078 (2011)

  42. 42

    Godden, T. M. et al. Coherent optical control of the spin of a single hole in a quantum dot. Preprint at arXiv:1106.6282.

  43. 43

    Greilich, A. et al. Nuclei-induced frequency focusing of electron spin coherence. Science 317, 1896–1899 (2007).

    ADS  Article  Google Scholar 

  44. 44

    Doty, M. F. et al. Hole–spin mixing in InAs quantum dot molecules. Phys. Rev. B 81, 035308 (2010).

    ADS  Article  Google Scholar 

Download references

Acknowledgements

This work was supported by a Multi-University Research Initiative (US Army Research Office; W911NF0910406) and the US Office of Naval Research.

Author information

Affiliations

Authors

Contributions

All authors were involved in the conception of the work and in writing the manuscript. A.S.B. grew and processed the samples. A.G., S.G.C. and D.K. performed the optical measurements. A.G., S.G.C. and D.G. performed data analysis and modelling.

Corresponding author

Correspondence to Daniel Gammon.

Ethics declarations

Competing interests

The authors declare no competing financial interests.

Rights and permissions

Reprints and Permissions

About this article

Cite this article

Greilich, A., Carter, S., Kim, D. et al. Optical control of one and two hole spins in interacting quantum dots. Nature Photon 5, 702–708 (2011). https://doi.org/10.1038/nphoton.2011.237

Download citation

Further reading

Search

Quick links

Nature Briefing

Sign up for the Nature Briefing newsletter — what matters in science, free to your inbox daily.

Get the most important science stories of the day, free in your inbox. Sign up for Nature Briefing