Temat: Quantum dot - Prolib Integro

Skocz do pozycji: 1.

Tytuł:: Optical bistability in double quantum dot molecule with inter-dot tunnelling
Autorzy:: Yu, Chunchao
Sun, Lihui
Zhang, Huafeng
Chen, Fang
Tematy:: optical bistability
quantum dot molecule
tunneling; Pokaż więcej
Wydawca:: Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Powiązania:: https://bibliotekanauki.pl/articles/174307.pdf Link otwiera się w nowym oknie
Opis:: We have theoretically studied the optical bistability behaviors under an external electric field and a coupling laser field in double quantum dot molecule system with π-type four energy levels. It can be adjusted by the system parameters such as the electronic cooperation parameter, the tunneling strength, the coupling laser field, the probe and coupling laser detuning. These results may be useful in the experiment and provide new types of all-optical switching.
Dostawca treści:: Biblioteka Nauki

Artykuł

na półce

Skocz do pozycji: 2.

Tytuł:: Spatio-Temporal Dynamics of Carrier Capture Processes: Simulation of Optical Signals
Autorzy:: Lengers, F.
Rosati, R.
Kuhn, T.
Reiter, D.
Tematy:: quantum dot
carrier capture
optical signals; Pokaż więcej
Wydawca:: Polska Akademia Nauk. Instytut Fizyki PAN
Powiązania:: https://bibliotekanauki.pl/articles/1033096.pdf Link otwiera się w nowym oknie
Opis:: We perform simulations of time-resolved optical experiments of carrier-capture processes in a quantum wire-dot system. Scattering of charge carriers with optical phonons of the quantum wire can result in transitions from the continuum states of the quantum wire to discrete states of the quantum dot. We treat the scattering of carriers with optical phonons within a Lindblad single-particle approach. By considering the coupling of carriers to a light field we are able to simulate pump-probe experiments which are shown to be capable of measuring the captured populations. We further discuss the influence of the Coulomb interaction on the obtained spectra.
Dostawca treści:: Biblioteka Nauki

Artykuł

na półce

Skocz do pozycji: 3.

Tytuł:: A numerical solution of the Poisson-Schrodinger problem for a vertical gated quantum dot
Autorzy:: Lis, K.
Bednarek, S.
Adamowski, J.
Tematy:: semiconductor quantum dot
quantum dots
Poisson-Schrodinger problem; Pokaż więcej
Wydawca:: Politechnika Gdańska
Powiązania:: https://bibliotekanauki.pl/articles/1964204.pdf Link otwiera się w nowym oknie
Opis:: We present a numerical solution of the Poisson-Schrodinger problem for a semiconductor nanostructure containing a single quantum dot. The main outcome of our work is the lateral confinement potential, which determines the electronic properties of the nanodevice. We study the real nanodevice with cylindrical symmetry, which allows us to solve the three-dimensional problem on a two-dimensional mesh. We discuss the self-consistency of the solution with respect to the distribution of ionized donors inside the nanodevice.
Dostawca treści:: Biblioteka Nauki

Artykuł

na półce

Skocz do pozycji: 4.

Tytuł:: Output-input properties of incident light on a defect dielectric slab with quantum dot nanostructure
Autorzy:: Jafarzadeh, Hossein
Tematy:: quantum dot nanostructure
optical bistability
optical multistability; Pokaż więcej
Wydawca:: Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Powiązania:: https://bibliotekanauki.pl/articles/174095.pdf Link otwiera się w nowym oknie
Opis:: We demonstrate output-input properties of incident light in a defect slab doped by three-level quantum dot nanostructure via quantum coherence and Fano-interference phenomena. Here, we will show that the output-input properties of the system can be adjusted by the Fano-interference strength, amplitude and the relative phase of the driving fields, respectively. Also, we consider the thickness effect of defect medium on controlling the output-input behaviors of probe light. Moreover, we realize that it is possible to switch between optical bistability and optical multistability by optimizing the conditions which are more practical in all-optical switching based nanoscale devices.
Dostawca treści:: Biblioteka Nauki

Artykuł

na półce

Skocz do pozycji: 5.

Tytuł:: Raman spectroscopy of CdTe/ZnTe quantum dot structures
Autorzy:: Zielony, E
Placzek-Popko, E
Kamyczek, P
Henrykowski, A
Karczewski, G
Tematy:: Raman spectroscopy
CdTe
ZnTe
quantum dot structures; Pokaż więcej
Wydawca:: Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Powiązania:: https://bibliotekanauki.pl/articles/174898.pdf Link otwiera się w nowym oknie
Opis:: Semiconductor low-dimensional structures of CdTe quantum dots (QDs) embedded in ZnTe matrix have been investigated by micro-Raman spectroscopy. A reference ZnTe sample (without dots) was also studied for comparison. Both samples were grown by a molecular beam epitaxy technique on the p-type GaAs substrate. The Raman measurements have been performed at room temperature. The samples were excited by an Ar2+ laser of 514.5 nm wavelength. The Raman spectra have been recorded for different acquisition parameters of the measurement. For the reference and QD sample localized longitudinal (LO) phonons of 210 cm–1 wavenumber associated with the ZnTe layer are observed. In the case of QD sample another broadband corresponding to the LO CdTe phonon related to the QD-layer appears at a wavenumber of 160 cm–1. Such behaviour does not exhibit the Raman spectra of the reference sample. Thus the Raman measurements confirm the presence of CdTe layer of quantum dots in the investigated material. Additionally, Raman spectra for both samples exhibit tellurium-related peaks at wavenumbers around 120 cm–1 and 140 cm–1, significantly increasing with laser time exposure. It is shown that the peaks are associated with the formation of Te aggregates on the ZnTe surface due to the laser damage in the ZnTe layer.
Dostawca treści:: Biblioteka Nauki

Artykuł

na półce

Skocz do pozycji: 6.

Tytuł:: Strain distributions in group IV and III-V semiconductor quantum dots
Autorzy:: Wijewardena Gamalath, K. A. I. L.
Fernando, M.A.I.P.
Tematy:: quantum dot
strain distribution
hydrostatic strain
biaxial strain; Pokaż więcej
Wydawca:: Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
Powiązania:: https://bibliotekanauki.pl/articles/411953.pdf Link otwiera się w nowym oknie
Opis:: A theoretical model was developed using GreenˇŚs function with an anisotropic elastic tensor to study the strain distribution in and around three dimensional semiconductor pyramidal quantum dots formed from group IV and III-V material systems namely, Ge on Si, InAs on GaAs and InP on AlP. A larger positive strain in normal direction which tends to zero beyond 6nm was observed for all three types while the strains parallel to the substrate were negative. For all the three types of quantum dots hydrostatic strain and biaxial strain along x and z directions were not linear but described a curve with a maximum positive value near the base of the quantum dot. The hydrostatic strain in x-direction is mostly confined within the quantum dot and practically goes to zero outside the edges of the quantum dot. For all the three types, the maximum hydrostatic and biaxial strains occur in x-direction around �{1nm and around 2nm in z-direction. The negative strain in x-direction although realtively weak penetrate more deeper to the substrate than hydrostatic strain.The group IV substrate gave larger hydrostatic and biaxial strains than the group III-V semiconductor combinations and InAs /GaAs was the most stable. The results indicated that the movements of atoms due to the lattice mismatch were strong for group III-V.
Dostawca treści:: Biblioteka Nauki

Artykuł

na półce

Skocz do pozycji: 7.

Tytuł:: Double tunneling induced transparency in the asymmetry quantum dot molecules
Autorzy:: Yu, C.
Huang, H.
Zhang, L.
Xu, D.
Tematy:: quantum dot molecule
slow light
tunneling induced transparency; Pokaż więcej
Wydawca:: Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Powiązania:: https://bibliotekanauki.pl/articles/173599.pdf Link otwiera się w nowym oknie
Opis:: Using the density matrix theory, we have studied the double tunneling induced transparency slow light in the double asymmetry quantum dot molecules. With applied electric field, double tunneling induced transparency occur in the same time. Four absorption peaks are found near the resonance energy level in the absorption spectrum and the absorption peak can be tuned by the applied electric field. The velocity and bandwidth of the multiple-windows slow light can also be controlled by the applied electric field. In our model, with T_e =0.1meV, we can get about 0.001c and 20GHz bandwidth in each transparency window. Such a property may be applied in all optical buffers, optical switching and filter.
Dostawca treści:: Biblioteka Nauki

Artykuł

na półce

Skocz do pozycji: 8.

Tytuł:: Dynamical and Steady State Processes of Probe Absorption-Dispersion in a Four-Level Quantum Dot Nanostructure
Autorzy:: Asadi Amirabadi, E.
Jamshidnejad, M.
Miraboutalebi, S.
Asadpour, S.
Tematy:: quantum dot nanostructure
absorption
dispersion
optical transient processes; Pokaż więcej
Wydawca:: Polska Akademia Nauk. Instytut Fizyki PAN
Powiązania:: https://bibliotekanauki.pl/articles/1032323.pdf Link otwiera się w nowym oknie
Opis:: In this paper, we investigated the transient electron population and the transient behaviour of the dispersion, absorption and refractive property of weak probe light in a four-level InGaN/GaN quantum dot nanostructure. In order to achieve the wave functions and their corresponding energy levels of the mentioned quantum dot nanostructure, the Schrödinger and Poisson equations is solved selfconsistently for carriers (here electron) in quantum dot. Our findings show that the properties of transient processes can be dramatically affected by parameters such as intensity, detuning and relative phase of applied fields. Our proposed scheme provides a realistic model for transient control of refraction index properties in a quantum dot nanostructure. These results may have potential applications in high speed optical switch for quantum information technologies.
Dostawca treści:: Biblioteka Nauki

Artykuł

na półce

Skocz do pozycji: 9.

Tytuł:: Versatile semiconductor quantum dots: synthesis, bioconjugation strategies and application
Autorzy:: Poddar, M.
Khurana, S.
Bose, S.
Nayak, R.
Tematy:: quantum dots
quantum dot synthesis
quantum dot bioconjugation
eco-friendly synthesis
photoluminescence
kropki kwantowe
synteza kropek kwantowych
biokoniugacja kropek kwantowych
ekologiczna synteza
fotoluminescencja; Pokaż więcej
Wydawca:: Stowarzyszenie Komputerowej Nauki o Materiałach i Inżynierii Powierzchni w Gliwicach
Powiązania:: https://bibliotekanauki.pl/articles/59116176.pdf Link otwiera się w nowym oknie
Opis:: Purpose: The present work aimed to synthesize organic and inorganic quantum dots (QDs) and discuss their bioconjugation strategies. Design/methodology/approach: We have prepared 3 different QDs, organic (Carbon [CQDs]) and inorganic (Cadmium Sulphide [CdS] and Zinc Mercury Selenide [ZnHgSe]) quantum dots (QDs) and bioconjugation through in-situ and ex-situ route. These QDs have been characterized through UV-Vis spectroscopy and photoluminescence (PL) emission spectra. Their surface functional groups have been identified through Fourier-transform infrared (FTIR) spectroscopy. The bioconjugated quantum dots were tested through PL emission shift, Agarose electrophoresis, and Bradford assay technique. Findings: Successful synthesized QDs, and their bioconjugation has been confirmed through the previously listed characterization techniques. There are distinct differences in their emission peak, FTIR spectroscopy, and Bradford assay, which confirms their successful bioconjugation. Research limitations/implications: These bioconjugated QDs are difficult to filter from their unconjugated counterpart. Bioconjugation steps are extremely crucial. Practical implications: These QDs could be utilized for highly effective biolabelling and bioimaging in-vivo as well as in-vitro applications. Originality/value: The synthesis has been majorly modified, and the bioconjugation has been prepared in a novel method. There is limited reported work with this much description of the differences in conjugated and unconjugated QDs.
Dostawca treści:: Biblioteka Nauki

Artykuł

na półce

Skocz do pozycji: 10.

Tytuł:: Computer simulation of the working cycle of a quantum controlled-NOT gate with two coupled quantum dots
Autorzy:: Moskal, S.
Bednarek, S.
Adamowski, J.
Tematy:: semiconductor quantum dot
quantum date operation
controlled-NOT (CNOT) gate; Pokaż więcej
Wydawca:: Politechnika Gdańska
Powiązania:: https://bibliotekanauki.pl/articles/1964205.pdf Link otwiera się w nowym oknie
Opis:: We discuss a possible realization of a quantum controlled-NOT gate with the use of two coupled quantum dots. Transitions between quantum states of a computational basis are driven by the microwave π-pulse. The parameters of the proposed nanodevice have been optimized in order to make the operation cycle of the gate as short as possible. Numerical solutions of the time-dependent Schrodinger equation allow us to simulate transitions between the quantum states which correspond to the subsequent stages of the gate's operation. The performed time-dependent simulations are a test of realizability of the quantum controlled-NOT gate in the nanodevice.
Dostawca treści:: Biblioteka Nauki

Artykuł

na półce

Informacja

Wyszukujesz frazę "Quantum dot" wg kryterium: Temat