One- and two-photon-excited time-resolved photoluminescence investigations of bulk and surface recombination dynamics in ZnSe

ABSTRACTWe report a study of dislocations in In-alloyed GaAs substrate material using space and time resolved photoluminescence (PL). PL intensity maps show that an isolated dislocation cluster is in the center of a dark region with a 50μm radius surrounded by a bright region with an outer radius of 150μm. Lifetime measurements were made in the bright and dark regions. Values as long as 3.5 ns and as short as 250 psec were observed in adjacent bright and dark regions. These measurements indicate that the PL intensity contrast is explained by lifetime variations in these features. This supports the view that the dislocation cluster acts as a source and sink for defects which govern the lifetime in the surrounding material. Temperature dependence of the lifetime indicates two different defects may be involved. Both of these produce deep levels, neither one of which is EL2. A surface passivation technique is used to show that surface recombination is not important to the PL intensity contrast.

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Superfluorescent Pulsed Emission from Biexcitons in an Ensemble of CuCl Quantum Dots

MRS Proceedings ◽

10.1557/proc-1208-o09-21 ◽

2009 ◽

Vol 1208 ◽

Author(s):

Kensuke Miyajima ◽

Shingo Saito ◽

Masaaki Ashida ◽

Tadashi Itoh

Keyword(s):

Quantum Dots ◽

Photoluminescence Spectra ◽

Fast Decay ◽

Time Resolved ◽

Resonant Energy ◽

Two Photon ◽

Time Profiles ◽

Photon Excitation ◽

Optical Kerr Gate ◽

Time Resolved Photoluminescence

AbstractTime-resolved photoluminescence spectra of an ensemble of CuCl quantum dots have been measured by an optical Kerr gate method. The excitation photon energy was tuned to resonant energy for two-photon excitation of biexcitons. We observed that the time profiles of biexciton bands were changed from an exponential fast decay to a pulsed shape. This result indicates a transition from amplified spontaneous emission to superfluorescence. These results will introduce a new field of coherent phenomena originating an ensemble of quantum dots.

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Recombination Dynamics of Surface-Related Excitonic States in Single ZnO Nanowires

Journal of Nanoscience and Nanotechnology ◽

10.1166/jnn.2008.n06 ◽

2008 ◽

Vol 8 (1) ◽

pp. 228-232 ◽

Cited By ~ 11

Author(s):

Tobias Voss ◽

Lars Wischmeier

Keyword(s):

Low Temperatures ◽

Optical Spectra ◽

Semiconductor Nanowires ◽

Emission Lines ◽

Time Resolved ◽

Photoluminescence Studies ◽

Different Diameters ◽

Excitonic States ◽

Time Resolved Photoluminescence ◽

Recombination Dynamics

With decreasing diameter the influence of surface-related effects becomes increasingly important for an understanding of the optical properties of semiconductor nanowires. We present time integrated and time resolved photoluminescence studies of single zincoxide nanowires with different diameters. We analyze the changes in the optical spectra for wires with different surface-to-volume ratios, present optical spectra of single wires at different excitation densities, and study the time-resolved dynamics of the surface related and donor-bound exciton related emission lines for a single nanowire at low temperatures.

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Photocarrier recombination dynamics in Cu2ZnSn(S,Se)4 and Cu(In,Ga)Se2 studied by temperature-dependent time resolved Photoluminescence (TR-PL)

2015 IEEE 42nd Photovoltaic Specialist Conference (PVSC) ◽

10.1109/pvsc.2015.7355693 ◽

2015 ◽

Author(s):

Mohammad Abdul Halim ◽

Muhammad Monirul Islam ◽

Xianjia Luo ◽

Takeaki Sakurai ◽

Noriyuki Sakai ◽

...

Keyword(s):

Temperature Dependent ◽

Time Resolved ◽

Time Resolved Photoluminescence ◽

Recombination Dynamics

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Photocarrier recombination dynamics in ternary chalcogenide CuInS2 quantum dots

Physical Chemistry Chemical Physics ◽

10.1039/c5cp00034c ◽

2015 ◽

Vol 17 (18) ◽

pp. 11981-11989 ◽

Cited By ~ 39

Author(s):

Jianhui Sun ◽

Michio Ikezawa ◽

Xiuying Wang ◽

Pengtao Jing ◽

Haibo Li ◽

...

Keyword(s):

Quantum Dots ◽

Transient Absorption ◽

Time Resolved ◽

Ternary Chalcogenide ◽

Femtosecond Transient Absorption ◽

Cuins2 Quantum Dots ◽

Time Resolved Photoluminescence ◽

Recombination Dynamics

Photocarrier recombination dynamics in ternary chalcogenide CuInS2 quantum dots (CIS QDs) was studied by means of femtosecond transient-absorption (TA) and nanosecond time-resolved photoluminescence (PL) spectroscopy.

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