scholarly journals Rapid Optical Spin Initialization of a Quantum Dot in the Voigt Geometry Coupled to a Two-Dimensional Semiconductor

2020 ◽  
Vol 10 (3) ◽  
pp. 1001
Author(s):  
Dionisis Stefanatos ◽  
Vasilios Karanikolas ◽  
Nikos Iliopoulos ◽  
Emmanuel Paspalakis

We study the interaction of a quantum dot in the Voigt configuration with a laser pulse and particularly analyze the potential for rapid spin initialization by putting the quantum dot near a molybdenum disulfide (MoS 2 ) monolayer. The MoS 2 monolayer influences the spontaneous decay rates of the quantum dot, leading to anisotropically enhanced decay rates, for the quantum dot’s electric dipole moments parallel and perpendicular to the layer. By solving the relevant density matrix equations, we find that high spin initialization fidelity is obtained at short times. The fidelity is significantly higher than when the quantum dot is in free-space vacuum. We examine two different cases of the interaction of the quantum dot with the applied optical field. First, we use a continuous wave laser field and determine for various quantum dot—MoS 2 layer distances the field strength that leads to acceptable fidelity levels. The effect of the quality of the MoS 2 material on the fidelity of spin initialization is also examined. We also study the interaction of the quantum dot with a laser pulse and apply numerical optimal control to obtain the time-dependent field strength, which leads to maximum final fidelity for short time intervals. The latter approach gives beneficial results in comparison to the continuous wave field excitation.

2014 ◽  
Vol 6 (2) ◽  
pp. 1178-1190
Author(s):  
A. JOHN PETER ◽  
Ada Vinolin

Simultaneous effects of magnetic field, pressure and temperature on the exciton binding energies are found in a 9.0 1.0 6.0 4.0 GaAs P / GaAs P quantum dot. Numerical calculations are carried out taking into consideration of spatial confinement effect. The cylindrical system is taken in the present problem with the strain effects. The electronic properties and the optical properties are found with the combined effects of magnetic field strength, hydrostatic pressure and temperature values. The exciton binding energies and the nonlinear optical properties are carried out taking into consideration of geometrical confinement and the external perturbations.Compact density approach is employed to obtain the nonlinear optical properties. The optical rectification coefficient is obtained with the photon energy in the presence of pressure, temperature and external magnetic field strength. Pressure and temperature dependence on nonlinear optical susceptibilities of generation of second and third order harmonics as a function of incident photon energy are brought out in the influence of magnetic field strength. The result shows that the electronic and nonlinear optical properties are significantly modified by the applications of external perturbations in a 9.0 1.0 6.0 4.0 GaAs P / GaAs P quantum dot.


DeKaVe ◽  
2013 ◽  
Vol 1 (2) ◽  
Author(s):  
Prayanto WH

Magazine is one of the forms of mass media that has fungsikomunikasi to convey information to mass audiences. The cover is an important element because it is through cover / cover one can guess the contents of the magazine, as well as further interested to know further information contained therein. On a magazine cover consists of drawings and writings are arranged in such a way that looks interesting and has meaning Press publications, especially magazines, today's not enough just to rely on the quality of news or manuscript, although verbal aspect is very important. It must be recognized that the visual aspects (design) as the cover / envelope has crucial role to capture the prospective reader. For the cover of a magazine is a window that shows the content information, can be either a text or photographs, illustrations, and design elements. The function of a magazine cover is to attract, dazzle prospective readers, by way influence the thoughts flow in a short time. So it's no wonder much current the magazine publisher who made the cover of such a way as to attract the attention of prospective readers. Thus the task of designers to magazine cover to create designs that attract the attention of the reader becomes increasingly severe. This study tries to analyze a visual on the front cover Magazine Graphic Design 'Concept' birthday inaugural edition by using the Roland Barthes' semiotic approach. As Roland Barthes (1984), any simple "design work (magazine cover)" continue to play in management of the sign. So that will generate a message (image) specific. Design cover, usually contains the elements of the sign in the form of objects, context of the environment, people or other beings who provide meaning to objects, and text (of writing) that reinforce the meaning.Keyword: cover, magazine Concept, semiotics


Author(s):  
T. Kiyan ◽  
C. Boit ◽  
C. Brillert

Abstract In this paper, a methodology based upon laser stimulation and a comparison of continuous wave and pulsed laser operation will be presented that localizes the fault relevant sites in a fully functional scan chain cell. The technique uses a laser incident from the backside to inject soft faults into internal nodes of a master-slave scan flip-flop in consequence of localized photocurrent. Depending on the illuminated type of the transistors (n- or p-type), injection of a logic ‘0’ or ‘1’ into the master or the slave stage of a flip-flop takes place. The laser pulse is externally triggered and can easily be shifted to various time slots in reference to clock and scan pattern. This feature of the laser diode allows triggering the laser pulse on the rising or the falling edge of the clock. Therefore, it is possible to choose the stage of the flip-flop in which the fault injection should occur. It is also demonstrated that the technique is able to identify the most sensitive signal condition for fault injection with a better time resolution than the pulse width of the laser, a significant improvement for failure analysis of integrated circuits.


Life ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 114
Author(s):  
Diana Escuder-Vieco ◽  
Juan M. Rodríguez ◽  
Irene Espinosa-Martos ◽  
Nieves Corzo ◽  
Antonia Montilla ◽  
...  

Holder pasteurization (HoP; 62.5 °C, 30 min) is commonly used to ensure the microbiological safety of donor human milk (DHM) but diminishes its nutritional properties. A high-temperature short-time (HTST) system was designed as an alternative for human milk banks. The objective of this study was to evaluate the effect of this HTST system on different nutrients and the bile salt stimulated lipase (BSSL) activity of DHM. DHM was processed in the HTST system and by standard HoP. Macronutrients were measured with a mid-infrared analyzer. Lactose, glucose, myo-inositol, vitamins and lipids were assayed using chromatographic techniques. BSSL activity was determined using a kit. The duration of HTST treatment had a greater influence on the nutrient composition of DHM than did the tested temperature. The lactose concentration and the percentage of phospholipids and PUFAs were higher in HTST-treated than in raw DHM, while the fat concentration and the percentage of monoacylglycerides and SFAs were lower. Other nutrients did not change after HTST processing. The retained BSSL activity was higher after short HTST treatment than that following HoP. Overall, HTST treatment resulted in better preservation of the nutritional quality of DHM than HoP because relevant thermosensitive components (phospholipids, PUFAs, and BSSL) were less affected.


2001 ◽  
Vol 89 (12) ◽  
pp. 8273-8278 ◽  
Author(s):  
Yuri Kaganovskii ◽  
Irena Antonov ◽  
Fredrick Bass ◽  
Michael Rosenbluh ◽  
Audrey Lipovskii

2006 ◽  
Vol 89 (4) ◽  
pp. 041113 ◽  
Author(s):  
T. Kettler ◽  
L. Ya. Karachinsky ◽  
N. N. Ledentsov ◽  
V. A. Shchukin ◽  
G. Fiol ◽  
...  

1999 ◽  
Vol 11 (11) ◽  
pp. 1345-1347 ◽  
Author(s):  
A.E. Zhukov ◽  
A.R. Kovsh ◽  
V.M. Ustinov ◽  
Yu.M. Shernyakov ◽  
S.S. Mikhrin ◽  
...  

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