Ground-state switching characteristics in vertically-coupled InGaN/GaN quantum dots

The rate equations are used to analyze the characteristics of a tandem consisting of a laser diode and a semiconductor optical amplifier made of a single heterostructure with quantum dots. The optimal value of the current distribution coefficient the amplifier and the laser, as well as the optimal resonator length that provides the highest output power of the tandem were determined. It is shown that the use of the tandem allows, at the same total consumed current, to significantly (more than 4 times for 1 A) increase the power emitted through the ground-state optical transition in comparison with that achievable with a laser diode solely being limited by the onset of lasing through an excited-state optical transition.

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Спиновая динамика отрицательно заряженных экситонов в квантовых точках InP/(In,Ga)P в магнитном поле

Физика твердого тела ◽

10.21883/ftt.2020.11.50054.149 ◽

2020 ◽

Vol 62 (11) ◽

pp. 1816

Author(s):

С.В. Некрасов ◽

Ю.Г. Кусраев ◽

И.А. Акимов ◽

L. Langer ◽

M. Kotur ◽

...

Keyword(s):

Magnetic Field ◽

Quantum Dots ◽

Circular Polarization ◽

Ground State ◽

Heavy Hole ◽

Spin Dynamics ◽

Nuclear Spins ◽

Time Resolved ◽

Exciton Ground State ◽

Charged Exciton

The dynamics of the photoluminescence negative circular polarization of the InP/(In,Ga)P quantum dots ensemble was studied. We find that in the time-resolved dependences of the polarization there are no oscillations in Voigt magnetic field. Also, with increasing field the polarization declines to zero. Such behavior is attributed to the peculiarities of the negatively charged exciton spin dynamics, particularly, to the fact that in the negatively charged exciton ground state the spin dynamics is governed by the heavy hole. We show that magnetic field depolarization of the photoluminescence occurs once the field of dynamically polarized nuclear spins acting on electron spins is surpassed.

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Modeling of the effect of bio-conjugation to anti-interleukin-10 antibodieson the photoluminescence of CdSe/ZnS quantum dots

MRS Proceedings ◽

10.1557/opl.2013.1177 ◽

2013 ◽

Vol 1617 ◽

pp. 145-150

Author(s):

Tetyana V. Torchynska ◽

Yuri V. Vorobiev ◽

Paul P. Horley

Keyword(s):

Quantum Dots ◽

Ground State ◽

Targeted Drug Delivery ◽

Blue Shift ◽

Interleukin 10 ◽

Theoretical Description ◽

Luminescence Spectra ◽

Scientific Interest ◽

Targeted Drug ◽

Nano Medicine

ABSTRACTBio-conjugated CdSe/ZnS core/shell quantum dots (QDs) attract essential scientific interest due to their possible nano-medicine applications, including selective highlighting of affected tissues and targeted drug delivery to the certain type of cells. The paper is focused on the theoretical description of the blue shift observed in the luminescence spectra of CdSe/ZnS QDs upon their bio-conjugation with the anti-interleukin-10 antibodies. We propose a model that describes the ground state of the exciton confined in a quantum dot and explaining the bio-conjugation phenomenon by the change of the effective confinement volume.

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