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1

Controlling the Biexciton-Exciton Cascade Kinetics in a Quantum Dot via Coupling to a Microcavity Optical Mode

100%

Sęk G., Krizhanovskii D., Kulakovskii V., Reitzenstein S., Kamp M.

Acta Physica Polonica A

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2016

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vol. 129

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issue 1a

A-44-A-47

EN

The luminescence of single and two exciton states in a quantum dot embedded in the active layer of a micropillar cavity has been investigated. Temperature tuning has been used to bring the energy states of the quantum dot and the cavity into resonance. Studying the resonance behavior of the exciton and biexciton transitions with cavity mode revealed a similar Purcell effect for both lines. The cavity-induced changes of the respective radiative lifetimes have been shown to allow for controlling the ratio between the single and two exciton occupation and their relative emission rates in a single quantum dot.

2

Room Temperature Carrier Kinetics in the W-type GaInAsSb/InAs/AlSb Quantum Well Structure Emitting in Mid-Infrared Spectral Range

73%

Syperek M., Ryczko K., Dallner M., Dyksik M., Motyka M., Kamp M., Höfling S., Misiewicz J., Sęk G.

Acta Physica Polonica A

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2016

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vol. 130

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issue 5

1224-1228

EN

Room temperature carrier kinetics has been investigated in the type-II W-design AlSb/InAs/Ga_{0.80}In_{0.20}As_{0.15}Sb_{0.85}/InAs/AlSb quantum well emitting in the mid-infrared spectral range (at 2.54 μ m). A time-resolved reflectance technique, employing the non-degenerated pump-probe scheme, has been used as a main experimental tool. Based on that, a primary carrier relaxation time of 2.3±0.2 ps has been found, and attributed to the initial carrier cooling process within the quantum well states, while going towards the ground state via the carrier-optical phonon scattering mechanism. The decay of a quasi-equilibrium carrier population at the quantum well ground states is primarily governed by two relaxation channels: (i) radiative recombination within distribution of spatially separated electrons and holes that occurs in the nanosecond time scale, and (ii) the hole tunnelling out of its confining potential, characterized by a 240±10 ps time constant.

3

GaAs-Based Quantum Well Exciton-Polaritons beyond 1 μm

73%

Pieczarka M., Podemski P., Musiał A., Ryczko K., Sęk G., Misiewicz J., Langer F., Höfling S., Kamp M., Forchel A.

Acta Physica Polonica A

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2013

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vol. 124

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issue 5

817-820

EN

Realization of the Bose-Einstein condensate can provide a way for creation of an inversion-free coherent light emitter with ultra-low threshold power. The currently considered solutions provide polaritonic emitters in a spectral range far below 1 μm limiting their application potential. Hereby, we present optical studies of InGaAs/GaAs based quantum well in a cavity structure exhibiting polaritonic eigenmodes from 5 to 160 K at a record wavelength exceeding 1 μm. The obtained Rabi splitting of 7 meV was almost constant with temperature, and the resulting coupling constant is close to the calculated QW exciton binding energy. This indicates the very strong coupling conditions explaining the observation of polaritons at temperatures where the exciton dissociation is already expected, and allows predicting that room temperature polaritons could still be formed in this kind of a system.

4

Effect of Dielectric Medium Anisotropy on the Polarization Degree of Emission from a Single Quantum Dash

59%

Mrowiński P., Tarnowski K., Olszewski J., Somers A., Kamp M., Höfling S., Reithmaier J., Urbańczyk W., Misiewicz J., Machnikowski P., Sęk G.

Acta Physica Polonica A

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2016

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vol. 129

|

issue 1a

A-48-A-52

EN

Excitonic emission from single InAs/InGaAlAs/InP quantum dashes has been investigated in the context of degree of linear polarization by post-growth modification of its surrounding dielectric medium. We present optical spectroscopy measurements on a symmetric squared pedestal structures (mesas), and asymmetric rectangular ones oriented parallel or perpendicular to the main in-plane axis of the dashes [1-10]. Polarization resolved microphotoluminescence shows a significant quantitative modification of the degree of linear polarization value from -20% up to 70%. These results have been confronted with calculations of the coupling between the exciton transition dipole moment and electromagnetic field distributed in the vicinity of a quantum dash inside a processed mesa.

5

Semiconductor Cavity Quantum Electrodynamics with Single Quantum Dots

59%

Reitzenstein S., Schneider C., Münch S., Kistner C., Strauss M., Huggenberger A., Franeck P., Weinmann P., Kamp M., Höfling S., Worschech L., Forchel A.

Acta Physica Polonica A

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2009

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vol. 116

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issue 4

445-450

EN

This paper summarizes recent progress achieved in the field of semiconductor cavity quantum electrodynamics with single quantum dots with the focus being on micropillar cavities. Light-matter interaction both in the strong and weak coupling regime is presented. Resonance tuning of the quantum dot by temperature, electric fields and magnetic fields is demonstrated while the strong coupling regime can be reached. Additionally, deterministic device integration of single positioned quantum dots is reported by a combination of site controlled quantum dot growth via directed nucleation and subsequent device alignment to overcome the degree of randomness of the quantum dot position in so far most common quantum dot-cavity systems.

Refine search results

Controlling the Biexciton-Exciton Cascade Kinetics in a Quantum Dot via Coupling to a Microcavity Optical Mode

Room Temperature Carrier Kinetics in the W-type GaInAsSb/InAs/AlSb Quantum Well Structure Emitting in Mid-Infrared Spectral Range

GaAs-Based Quantum Well Exciton-Polaritons beyond 1 μm

Effect of Dielectric Medium Anisotropy on the Polarization Degree of Emission from a Single Quantum Dash

Semiconductor Cavity Quantum Electrodynamics with Single Quantum Dots