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.

  • Article
  • Published:

A light-hole exciton in a quantum dot

Subjects

Abstract

A light-hole exciton is a quasiparticle formed from a single electron bound to a single light hole. This type of fundamental excitation, if confined inside a semiconductor quantum dot, could be advantageous in quantum information science and technology. However, it has been difficult to access it so far, because confinement and strain in conventional quantum dots favour a ground-state single-particle hole with a predominantly heavy-hole character. Here we demonstrate the creation of a light-hole exciton ground state by applying elastic stress to an initially unstrained quantum dot. Its signature is clearly distinct from that of the well-known heavy-hole exciton and consists of three orthogonally polarized bright optical transitions and a fine-structure splitting of hundreds of microelectronvolts between in-plane and out-of-plane components. This work paves the way for the exploration of the fundamental properties and of the potential relevance of three-dimensionally confined light-hole states in quantum technologies.

This is a preview of subscription content, access via your institution

Access options

Buy this article

Prices may be subject to local taxes which are calculated during checkout

Figure 1: A quantum dot with a light-hole exciton ground state.
Figure 2: Representative micro-photoluminescence spectra of heavy-hole and light-hole excitons in single GaAs/AlGaAs quantum dots.
Figure 3: Representative polarization-resolved micro-photoluminescence spectra of light-hole excitons in a magnetic field applied along the growth direction (Faraday configuration).
Figure 4: Calculation results using the experimental quantum-dot structure.
Figure 5: Strain tuning of a light-hole exciton.

Similar content being viewed by others

References

  1. Zrenner, A. et al. Coherent properties of a two-level system based on a quantum-dot photodiode. Nature 418, 612–614 (2002).

    Article  ADS  Google Scholar 

  2. Ramsay, A. J. A review of the coherent optical control of the exciton and spin states of semiconductor quantum dots. Semicond. Sci. Technol. 25, 103001 (2010).

    Article  ADS  Google Scholar 

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

    Article  ADS  Google Scholar 

  4. 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).

    Article  ADS  Google Scholar 

  5. Nowack, K. C., Koppens, F. H. L., Nazarov, Y. V. & Vandersypen, L. M. K. Coherent control of a single electron spin with electric fields. Science 318, 1430–1433 (2007).

    Article  ADS  Google Scholar 

  6. Laurent, S. et al. Electrical control of hole spin relaxation in charge tunable InAs/GaAs quantum dots. Phys. Rev. Lett. 94, 147401 (2005).

    Article  ADS  Google Scholar 

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

    Article  ADS  Google Scholar 

  8. Greve, K. D. et al. Ultrafast coherent control and suppressed nuclear feedback of a single quantum dot hole qubit. Nature Phys. 7, 872–878 (2011).

    Article  ADS  Google Scholar 

  9. Michler, P. et al. A quantum dot single-photon turnstile device. Science 290, 2282–2285 (2000).

    Article  ADS  Google Scholar 

  10. Akopian, N. et al. Entangled photon pairs from semiconductor quantum dots. Phys. Rev. Lett. 96, 130501 (2006).

    Article  ADS  Google Scholar 

  11. Salter, C. L. et al. An entangled-light-emitting diode. Nature 465, 594–597 (2010).

    Article  ADS  Google Scholar 

  12. Vrijen, R. & Yablonovitch, E. A spin-coherent semiconductor photo-detector for quantum communication. Physica E 10, 569–575 (2001).

    Article  ADS  Google Scholar 

  13. Sleiter, D. & Brinkman, W. F. Using holes in GaAs as qubits: An estimate of the Rabi frequency in the presence of an external rf field. Phys. Rev. B 74, 153312 (2006).

    Article  ADS  Google Scholar 

  14. Kosaka, H. et al. Spin state tomography of optically injected electrons in a semiconductor. Nature 457, 702–705 (2009).

    Article  ADS  Google Scholar 

  15. Reiter, D. E., Kuhn, T. & Axt, V. M. Coherent control of a single Mn spin in a quantum dot via optical manipulation of the light hole exciton. Phys. Rev. B 83, 155322 (2011).

    Article  ADS  Google Scholar 

  16. Schmidt, K. H., Medeiros-Ribeiro, G., Oestreich, M., Petroff, P. M. & Döhler, G. H. Carrier relaxation and electronic structure in InAs self-assembled quantum dots. Phys. Rev. B 54, 11346–11353 (1996).

    Article  ADS  Google Scholar 

  17. Karlsson, K. F. et al. Fine structure of exciton complexes in high-symmetry quantum dots: Effects of symmetry breaking and symmetry elevation. Phys. Rev. B 81, 161307(R) (2010).

    Article  ADS  Google Scholar 

  18. Besombes, L., Kheng, K. & Martrou, D. Exciton and biexciton fine structure in single elongated islands grown on a vicinal surface. Phys. Rev. Lett. 85, 425–428 (2000).

    Article  ADS  Google Scholar 

  19. Belhadj, T. et al. Impact of heavy hole-light hole coupling on optical selection rules in GaAs quantum dots. Appl. Phys. Lett. 97, 051111 (2010).

    Article  ADS  Google Scholar 

  20. Li, L. et al. Control of polarization and dipole moment in low-dimensional semiconductor nanostructures. Appl. Phys. Lett. 95, 221116 (2009).

    Article  ADS  Google Scholar 

  21. Ridha, P. et al. Polarization properties of columnar quantum dots: Effects of aspect ratio and compositional contrast. IEEE J. Quant. Electron. 46, 197–204 (2010).

    Article  ADS  Google Scholar 

  22. Troncale, V., Karlsson, K. F., Pelucchi, E., Rudra, A. & Kapon, E. Control of valence band states in pyramidal quantum dot-in-dot semiconductor heterostructures. Appl. Phys. Lett. 91, 241909 (2007).

    Article  ADS  Google Scholar 

  23. Huo, Y. H., Rastelli, A. & Schmidt, O. G. Ultra-small excitonic fine structure splitting in highly symmetric quantum dots on GaAs(001) substrate. Appl. Phys. Lett. 102, 152105 (2013).

    Article  ADS  Google Scholar 

  24. Owen, D. L., Lackner, D., Pitts, O. J., Watkins, S. P. & Mooney, P. M. In-place bonding of GaAs/InGaAs/GaAs heterostructures to GaAs(001). Semicond. Sci. Technol. 24, 035011 (2009).

    Article  ADS  Google Scholar 

  25. Zander, T. et al. Epitaxial quantum dots in stretchable optical microcavities. Opt. Express 17, 22452–22461 (2009).

    Article  ADS  Google Scholar 

  26. Ding, F. et al. Tuning the exciton binding energies in single self-assembled InGaAs/GaAs quantum dots by piezoelectric-induced biaxial stress. Phys. Rev. Lett. 104, 067405 (2010).

    Article  ADS  Google Scholar 

  27. Bir, G. L. & Pikus, G. E. Symmetry and Strain-induced Effects in Semiconductors (Wiley, 1974).

    Google Scholar 

  28. Meier, F. & Zakharchenva, B. P. (eds) Optical Orientation (Modern Physics in Condensed Matter Science, Vol 8, Elsevier Science, 1984).

  29. 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).

    Article  ADS  Google Scholar 

  30. Witek, B. J. et al. Measurement of the g-factor tensor in a quantum dot and disentanglement of exciton spins. Phys. Rev. B 84, 195305 (2011).

    Article  ADS  Google Scholar 

  31. Bester, G., Nair, S. & Zunger, A. Pseudopotential calculation of the excitonic fine structure of million-atom self-assembled In1−xGaxAs/GaAs quantum dots. Phys. Rev. B 67, 161306(R) (2003).

    Article  ADS  Google Scholar 

  32. Bester, G. Electronic excitations in nanostructures: An empirical pseudopotential based approach. J. Phys. Condens. Matter 21, 023202 (2009).

    Article  ADS  Google Scholar 

  33. Rastelli, A. et al. Hierarchical self-assembly of GaAs/AlGaAs Quantum dots. Phys. Rev. Lett. 92, 166104 (2004).

    Article  ADS  Google Scholar 

  34. Tonin, C. et al. Polarization properties of excitonic qubits in single self-assembled quantum dots. Phys. Rev. B. 85, 155303 (2012).

    Article  ADS  Google Scholar 

  35. Trotta, R. et al. Nanomembrane quantum-light-emitting diodes integrated onto piezoelectric actuators. Adv. Mater. 24, 2668–2672 (2012).

    Article  Google Scholar 

Download references

Acknowledgements

We acknowledge P. Atkinson, Ch. Deneke, D. J. Thurmer and R. Engelhard for assistance with the molecular beam epitaxy, D. Grimm, B. Martin and S. Harazim for assistance in clean room maintenance, and G. Katsaros and R. Rezaev for fruitful discussions. This work was financially supported by the BMBF project QuaHL-Rep (Contracts no. 01BQ1032 and 01BQ1034), the DFG FOR730, the FOM (VIDI Grant), the European Union Seventh Framework Programme 209 (FP7/2007-2013) under Grant Agreement No. 601126 210 (HANAS) and the ERANET project QOptInt.

Author information

Authors and Affiliations

Authors

Contributions

Y.H.H. grew and processed samples, measured micro-photoluminescence, and analysed data supported by S.K., J.X.Z., E.Z., R.T. and F.D., under supervision of A.R. and O.G.S. B.J.W. carried out micro-photoluminescence in magnetic field supported by N.A. and V.Z. and provided insightful interpretation of the experimental and theoretical results. J.R.C., R.S. and G.B. performed pseudopotential calculations and developed the mesoscopic model. R.G., D.K. and J.S. performed X-ray diffraction measurements. All authors discussed the results and contributed to the manuscript. A.R. conceived and coordinated the project, triggered by V.Z. and N.A.

Corresponding authors

Correspondence to Y. H. Huo, B. J. Witek, G. Bester or A. Rastelli.

Ethics declarations

Competing interests

The authors declare no competing financial interests.

Supplementary information

Supplementary Information

Supplementary Information (PDF 3926 kb)

Rights and permissions

Reprints and permissions

About this article

Cite this article

Huo, Y., Witek, B., Kumar, S. et al. A light-hole exciton in a quantum dot. Nature Phys 10, 46–51 (2014). https://doi.org/10.1038/nphys2799

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1038/nphys2799

This article is cited by

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