Intersublevel transitions in semiconductor quantum dots are transitions of a charge carrier between quantum dot confined states. In InAs/GaAs self-assembled quantum dots, optically active intersublevel transitions occur in the mid-infrared spectral range. These transitions can provide a new insight on the physics of semiconductor quantum dots and offer new opportunities to develop mid-infrared devices. A key feature characterizing intersublevel transitions is the coupling of the confined carriers to phonons. We show that the effect of the strong coupling regime for the electron–optical phonon interaction and the formation of mixed electron–phonon quasi-particles called polarons drastically affect and control the dynamical properties of quantum dots. The engineering of quantum dot relaxation rates through phonon coupling opens the route to the realization of new devices like mid-infrared polaron lasers. We finally show that the measurement of intersublevel absorption is not limited to quantum dot ensembles and that the intersublevel ultrasmall absorption of a single quantum dot can be measured with a nanometer scale resolution by using phonon emission as a signature of the absorption.
Les transitions inter-sous-niveaux dans les boîtes quantiques de semi-conducteurs sont les transitions que peut effectuer un porteur de charge entre niveaux confinés. Dans les boîtes quantiques auto-assemblées InAs/GaAs, les transitions inter-sous-niveaux optiquement actives peuvent être observées dans la gamme spectrale de l'infrarouge moyen. Ces transitions dévoilent de nouvelles facettes de la physique des boîtes quantiques de semi-conducteurs et ouvrent de nouvelles perspectives pour le développement de composants moyen-infrarouges. Une caractéristique clef des transitions inter-sous-niveaux est le couplage des porteurs de charges confinés avec les phonons. Nous montrons que le régime de couplage fort pour l'interaction électron–phonon optique et la formation de particules mixtes électron–phonon appelées polarons gouvernent la dynamique des boîtes quantiques. L'ingénierie des taux de relaxation dans les boîtes quantiques, obtenue au travers du couplage électron–phonon, ouvre la voie à la réalisation de nouveaux dispositifs tels qu'un laser moyen-infrarouge à polarons. Nous montrons enfin que la mesure de l'absorption inter-sous-niveaux n'est pas limitée à des ensembles de boîtes quantiques et que l'absorption ultrafaible d'une boîte quantique unique peut être mesurée avec une résolution spatiale nanométrique en exploitant l'émission de phonons comme signature de l'absorption.
Mot clés : Boîte quantique, Transitions intersousniveaux, Polaron, Moyen infrarouge
Philippe Boucaud 1; Sébastien Sauvage 1; Julien Houel 1
@article{CRPHYS_2008__9_8_840_0, author = {Philippe Boucaud and S\'ebastien Sauvage and Julien Houel}, title = {Intersublevel transitions in self-assembled quantum dots}, journal = {Comptes Rendus. Physique}, pages = {840--849}, publisher = {Elsevier}, volume = {9}, number = {8}, year = {2008}, doi = {10.1016/j.crhy.2008.10.005}, language = {en}, }
Philippe Boucaud; Sébastien Sauvage; Julien Houel. Intersublevel transitions in self-assembled quantum dots. Comptes Rendus. Physique, Volume 9 (2008) no. 8, pp. 840-849. doi : 10.1016/j.crhy.2008.10.005. https://comptes-rendus.academie-sciences.fr/physique/articles/10.1016/j.crhy.2008.10.005/
[1] Spectroscopy of quantum levels in charge-tunable InGaAs quantum dots, Phys. Rev. Lett., Volume 73 (1994) no. 16, pp. 2252-2255
[2] Intraband absorption in n-doped InAs/GaAs quantum dots, Appl. Phys. Lett., Volume 71 (1997) no. 19, pp. 2785-2787
[3] Mid-infrared photoconductivity in InAs quantum dots, Appl. Phys. Lett., Volume 70 (1997) no. 14, pp. 1861-1863
[4] Infrared spectroscopy of intraband transitions in self-organized InAs/GaAs quantum dots, J. Appl. Phys., Volume 82 (1997) no. 7, pp. 3396-3401
[5] Temperature dependence of intersublevel absorption in InAs/GaAs self-assembled quantum dots, Appl. Phys. Lett., Volume 80 (2002) no. 24, pp. 4620-4622
[6] Infrared photodetection with semiconductor self-assembled quantum dots, C. R. Physique, Volume 4 (2003) no. 10, pp. 1133-1154
[7] Second-harmonic generation resonant with s-p transition in InAs/GaAs self-assembled quantum dots, Phys. Rev. B, Volume 63 (2001) no. 11, p. 113312
[8] Third-harmonic generation in InAs/GaAs self-assembled quantum dots, Phys. Rev. B, Volume 59 (1999) no. 15, pp. 9830-9833
[9] Electron relaxation in a quantum dot: Significance of multiphonon processes, Phys. Rev. B: Conden. Matter, Volume 46 (1992) no. 11, pp. 7260-7263
[10] Strong electron–phonon coupling regime in quantum dots: Evidence for everlasting resonant polarons, Phys. Rev. Lett., Volume 83 (1999) no. 20, pp. 4152-4155
[11] Intrinsic mechanism for the poor luminescence properties of quantum-box systems, Phys. Rev. B, Volume 44 (1991) no. 19, pp. 10945-10948
[12] Saturation of intraband absorption and electron relaxation time in n-doped InAs/GaAs self-assembled quantum dots, Appl. Phys. Lett., Volume 73 (1998) no. 26, pp. 3818-3820
[13] Long polaron lifetime in InAs/GaAs self-assembled quantum dots, Phys. Rev. Lett., Volume 88 (2002) no. 17, p. 177402
[14] Phonon bottleneck in quantum dots: Role of lifetime of the confined optical phonons, Phys. Rev. B, Volume 59 (1999) no. 7, pp. 5069-5073
[15] Intraband relaxation via polaron decay in InAs self-assembled quantum dots, Phys. Rev. B: Conden. Matter Mater. Phys., Volume 70 (2004) no. 16, p. 161305
[16] Polaron relaxation in self-assembled quantum dots: Breakdown of the semiclassical model, Phys. Rev. B: Conden. Matter Mater. Phys., Volume 76 (2007) no. 24, p. 241304
[17] Intersublevel polaron laser with InAs/GaAs self-assembled quantum dots, Appl. Phys. Lett., Volume 88 (2006) no. 6, p. 063106
[18] Fast decoherence of slowly relaxing polarons in semiconductor InAs quantum dots, Europhys. Lett., Volume 70 (2005) no. 3, pp. 390-396
[19] Intersublevel polaron dephasing in self-assembled quantum dots, Phys. Rev. B: Conden. Matter Mater. Phys., Volume 77 (2008) no. 4, p. 041307
[20] Ultraweak-absorption microscopy of a single semiconductor quantum dot in the midinfrared range, Phys. Rev. Lett., Volume 99 (2007) no. 21, p. 217404
Cited by Sources:
Comments - Policy