PhD scholarship in Nano-Photonic Circuits for Optical Communication
Trabajo en HOVEDSTADEN (Dinamarca) de Profesores de universidades y de la enseñanza superior
Clasificación del trabajo:Profesionales científicos e intelectuales : Profesionales de la enseñanza : Profesores de universidades y de la enseñanza superior : Profesores de universidades y de la enseñanza superior. Arbejde, der forudsætter viden på højeste niveau inden for pågældende område : Undervisning og pædagogisk arbejde : Undervisning og forskning ved universiteter og højere læreranstalter : Undervisning og forskning på universiteter og højere læreranstalter.
Descripción de la oferta de trabajo:
The Electromagnetic Systems (EMS) group at DTU Electrical Engineering invites applications for a 3-year PhD position that focuses on the development and synthesis of photonic circuits. The PhD will be a in close collaboration with the research centre NATEC (NAnophotonics for Terabit Communications) from DTU Fotonik. Quantum Dots (QDs) are a special kind of single-photon sources and belong to the class of deterministic sources. Although the concept of a single photon was already proposed in 1900 by Planck, a true single-photon source was not created in isolation until 1974, and in 1977, evidence of single-photon emission from sodium atoms was observed for the first time. Single-photon sources are indispensable for photonic quantum circuits and a major driver of the current research into single-photon sources and detectors is the explosive growth of the field of quantum-information science over the last few decades, especially quantum cryptography. The field has reached a certain level of maturity. Today, it is possible to find nearly ideal devices when only one parameter is important, but performance of other parameters is often compromised. Specifically, for sources, while initial efforts were focused mostly on increasing brightness and generation efficiency, current improvement efforts are more driven by the requirements for particular applications and often deal directly with improving more than one characteristic simultaneously. These multi-parameter efforts include better single-photon state accuracy, and higher degrees of indistinguishability of single-photon output states, which is particularly important for many quantum-information applications. When single-photon emission is desired, some external control is used to put the system into an excited state that will emit a single photon upon relaxation to some lower-energy state. While this is quite well mastered, the problem occurs in the collection and efficient light extraction, which poses a major challenge in the design of single-photon sources. This is the starting point for the proposed PhD thesis. It shall focus on the problem of collection efficiency and light extraction, but is not limited to it. Responsibilities and tasks The PhD comprises the following mains tasks: •The efficient simulation of QDs, coupling structures and related photonic circuits The candidate shall setup a simulation model and investigate how to efficiently simulate the electrically large structures that often comprise several wavelengths. •Design and optimization of coupling structures to improve the collection efficiency and light extraction Taking as starting point typical concepts from microwave circuits and antennas, it shall be investigated if and how these approaches can be transferred to optical systems. Typical examples are lens, cavity-backed, or horn antennas but also other microwave matching circuits shall be considered. •Tuning elements The exact location of QDs when manufacturing a single-photon source is a serious problem. For example, in the case of micro-cavity pillars, the QD should be located in the centre of the cavity. However, this cannot be guaranteed, resulting in a lower efficiency and de-tuning of the source. Tuning elements are an essential element to account for manufacturing tolerances in the case of very narrow-band systems and for achieving optimal functioning of devices. The goal of this task is to study which possibilities exist and how to implement them for fine tuning the QD sources. Qualifications Candidates should hold a MSc in electrical engineering or a similar degree with an academic level equivalent to the MSc in electrical engineering. Additionally, the candidate must have knowledge of electromagnetics and circuit design and must have experience with the simulations tools HFSS and/or CST. Experience in writing technical reports and scientific publications is an asset. Approval and Enrolment PhD scholarships are subject to academic approval, and
Servicio de empleo de origen:AMS, Servicios Públicos de Empleo, Dinamarca.