%0 Journal Article %1 Schaller2007 %A Schaller, R. D. %A Pietryga, J. M. %A Klimov, V. I. %C Los Alamos Natl Lab, Div Chem, Los Alamos, NM 87545 USA. Schaller, RD, Los Alamos Natl Lab, Div Chem, POB 1663, Los Alamos, NM 87545 USA. rdsx@lanl.gov klimov@lanl.gov %D 2007 %J Nano Lett. %K CDSE COLLOIDAL EFFICIENCY; ELECTRON EXCITON GAIN; GENERATION; INP MULTIPLE NANOCRYSTALS; OPTICAL PBSE PBSE; PHOTOLUMINESCENCE; RELAXATION; SEMICONDUCTOR TIME-RESOLVED %N 11 %P 3469-3476-- %T Carrier multiplication in InAs nanocrystal quantum dots with an onset defined by the energy conservation limit %V 7 %X Carrier multiplication (CM) is a process in which absorption of a single photon produces not just one but multiple electron-hole pairs (excitons). This effect is a potential enabler of next-generation, high-efficiency photovoltaic and photocatalytic systems. On the basis of energy conservation, the minimal photon energy required to activate CM is two energy gaps (2E(g)). Here, we analyze CM onsets for nanocrystal quantum dots (NQDs) based upon combined requirements imposed by optical selection rules and energy conservation and conclude that materials with a significant difference between electron and hole effective masses such as III-V semiconductors should exhibit a CM threshold near the apparent 2E(g) limit. Further, we discuss the possibility of achieving sub-2E(g) CM thresholds through strong exciton-exciton attraction, which is feasible in NQDs. We report experimental studies of exciton dynamics (Auger recombination, intraband relaxation, radiative recombination, multiexciton generation, and biexciton shift) in InAs NQDs and show that they exhibit a CM threshold near 2E(g).

@article{Schaller2007, abstract = {Carrier multiplication (CM) is a process in which absorption of a single photon produces not just one but multiple electron-hole pairs (excitons). This effect is a potential enabler of next-generation, high-efficiency photovoltaic and photocatalytic systems. On the basis of energy conservation, the minimal photon energy required to activate CM is two energy gaps (2E(g)). Here, we analyze CM onsets for nanocrystal quantum dots (NQDs) based upon combined requirements imposed by optical selection rules and energy conservation and conclude that materials with a significant difference between electron and hole effective masses such as III-V semiconductors should exhibit a CM threshold near the apparent 2E(g) limit. Further, we discuss the possibility of achieving sub-2E(g) CM thresholds through strong exciton-exciton attraction, which is feasible in NQDs. We report experimental studies of exciton dynamics (Auger recombination, intraband relaxation, radiative recombination, multiexciton generation, and biexciton shift) in InAs NQDs and show that they exhibit a CM threshold near 2E(g).}, added-at = {2009-02-13T13:09:53.000+0100}, address = {Los Alamos Natl Lab, Div Chem, Los Alamos, NM 87545 USA. Schaller, RD, Los Alamos Natl Lab, Div Chem, POB 1663, Los Alamos, NM 87545 USA. rdsx@lanl.gov klimov@lanl.gov}, author = {Schaller, R. D. and Pietryga, J. M. and Klimov, V. I.}, biburl = {https://www.bibsonomy.org/bibtex/25d87f575125d877bd1bb11cc57085326/almailer}, comment = {Nov Article Carrier multiplication in InAs nanocrystal quantum dots with an onset defined by the energy conservation limit Schaller, Richard D. Pietryga, Jeffrey M. Klimov, Victor I. English}, description = {Initial Import}, file = {:Schaller2007.pdf:PDF}, interhash = {4e4ce3230cf7e2d66d4e1a5c2a461805}, intrahash = {5d87f575125d877bd1bb11cc57085326}, issn = {1530-6984}, journal = {Nano Lett.}, keywords = {CDSE COLLOIDAL EFFICIENCY; ELECTRON EXCITON GAIN; GENERATION; INP MULTIPLE NANOCRYSTALS; OPTICAL PBSE PBSE; PHOTOLUMINESCENCE; RELAXATION; SEMICONDUCTOR TIME-RESOLVED}, number = 11, owner = {s0346678}, pages = {3469-3476--}, refid = {2}, timestamp = {2009-02-13T13:09:55.000+0100}, title = {Carrier multiplication in InAs nanocrystal quantum dots with an onset defined by the energy conservation limit}, volume = 7, year = 2007 }