Polariton states bound to defects in GaAs/AlAs planar microcavities

We report on polariton states bound to defects in planar GaAs/AlAs microcavities grown by molecular beam epitaxy. The defect types relevant for the spatial polariton dynamics in these structures are cross-hatch misfit dislocations, and point-like defects extended over several micrometers. We attribute the latter defects to Ga droplets emitted occasionally by the Ga cell during the growth. These defects, also known as oval defects, result in a dome-like local modulation of surface, which is translated into the cavity structure and leads to a lateral modulation of the cavity polariton energy of up to 15\,meV. The resulting spatially localized potential landscape for the in-plane polariton motion creates a series of bound states. These states were characterized by spectrally resolved transmission imaging in real and reciprocal space, and reveal the spatial potential created by the defects. Interestingly, the defect states exhibit long lifetimes in the 10ps range, which we attribute to a spatially smooth confinement potential

The Consequences of Failing: A Memoir

Failing is part of our human nature. I have never met a person who has never failed at something. Sometimes when I look back at my failures I feel like crying, and other times I laugh at the mistakes that I have made. But no matter the type of failure I have suffered, I have learned one thing. Failures, along with successes, have shaped me into the person I am today. When I fail, I often fall. But each fall is a chance for me to get back up. I don’t plan to stop failing any time soon. Just like failures, each breath we take keeps us functional, both body and mind. As we continue to live we acquire more and more memories. Therefore, in a roundabout way, memories serve as a consequence to both our failures and our breaths. And as each breath is unique to us, so is each memory. With this in mind, the purpose of this project is to explore some of the events that have occurred in my life, and write them down according to how I experienced them. While others in my life may have experienced some of the same events in a different manner, the goal of this project is to use perspective and memory to illustrate my perception of the events. I intend to use this project as an exercise to immobilize parts of my past by stopping time for a moment so that my voice might give breath to the telling

Scalable gate architecture for densely packed semiconductor spin qubits

We demonstrate a 12 quantum dot device fabricated on an undoped Si/SiGe heterostructure as a proof-of-concept for a scalable, linear gate architecture for semiconductor quantum dots. The device consists of 9 quantum dots in a linear array and 3 single quantum dot charge sensors. We show reproducible single quantum dot charging and orbital energies, with standard deviations less than 20% relative to the mean across the 9 dot array. The single quantum dot charge sensors have a charge sensitivity of 8.2 x 10^{-4} e/root(Hz) and allow the investigation of real-time charge dynamics. As a demonstration of the versatility of this device, we use single-shot readout to measure a spin relaxation time T1 = 170 ms at a magnetic field B = 1 T. By reconfiguring the device, we form two capacitively coupled double quantum dots and extract a mutual charging energy of 200 microeV, which indicates that 50 GHz two-qubit gate operation speeds are feasible

A Reconfigurable Gate Architecture for Si/SiGe Quantum Dots

We demonstrate a reconfigurable quantum dot gate architecture that incorporates two interchangeable transport channels. One channel is used to form quantum dots and the other is used for charge sensing. The quantum dot transport channel can support either a single or a double quantum dot. We demonstrate few-electron occupation in a single quantum dot and extract charging energies as large as 6.6 meV. Magnetospectroscopy is used to measure valley splittings in the range of 35-70 microeV. By energizing two additional gates we form a few-electron double quantum dot and demonstrate tunable tunnel coupling at the (1,0) to (0,1) interdot charge transition.Comment: Related papers at http://pettagroup.princeton.ed

Internal marketing and talent management as integral elements of employer branding strategies

The paper presents internal marketing and talent management as key elements determining effective introduction of employer branding strategy. Nowadays tendencies to interdisciplinarity force organizations to search for concepts from different areas of science and combine them for most effective market performance. That is the reason for presentation of two aspects of employer branding – from HRM and marketing perspectives, in the paper. The paper is aimed at presentation and discussion of internal marketing and talent management as elements of overall strategy of organisation in the scope of its competitive advantage gaining. When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/3550

Extensions of Effect Algebra Operations

We study the set of all positive linear operators densely defined in an infinite-dimensional complex Hilbert space. We equip this set with various effect algebraic operations making it a generalized effect algebra. Further, sub-generalized effect algebras and interval effect algebras with respect of these operations are investigated