Doctoral student in physics within the discipline of THz electron-spin-resonance ellipsometry - Hiring in process/Finished, not possible to apply

The PhD position is placed at the Division of Solid State Physics in the Department of Physics, where extensive research is carried out centred on various aspects of nanophysics, ranging from materials science to quantum physics to various applications. The department also leads NanoLund, Lund University's major interdisciplinary research centre on nanoscience and nanotechnology. The Lund Nano Lab provides a central and shared facility for the production of materials and components at the nanoscale. The department also has a strong involvement in undergraduate education, not least in the Master of Science in Engineering Nanoscience programme at LTH.

Research area

THz Ellipsometry and its application for characterising semiconductor materials and device heterostructures is a focus in materials sciences at the division. One of the advanced methods to access electronic transport properties of the materials is the optical Hall effect. It has been applied to two-dimensional semiconductor systems like nitride-based high-electron-mobility transistors and graphene, as well as to wide-bandgap semiconductors with low crystal symmetry like e.g. Ga2O3. These materials and related device structures are the basis for next-generation high-frequency and high-power electronics which is developed in cooperation with leading Swedish industrial partners to address the needs for a green energy and wireless communication systems.

Defect characterization in semiconductors through measurements of electron spin resonances by THz ellipsometry at magnetic fields up to 8T (high-field EPR) is a new direction that is currently being explored. The research consists of development of world-unique THz-EPR ellipsometry equipment and strategies based on polarization optics. The goal is to characterize spin in semiconductor hetero- and nano-structures, not accessible by standard EPR methods, and to get a better understanding of electronic defects with a focus on ultrawide bandgap semiconductors with low crystal symmetry.

The work is focused on fundamental research strongly connected to future concepts for application in quantum technology.

More information can be found at:

https://liu.se/en/research/semiconductor-device-materials, www.ftf.lth.se, www.nano.lu.se

Work duties

The main duties of doctoral students are to devote themselves to their research studies, which includes participating in research projects and third cycle courses. The work duties can also include teaching and other departmental duties (no more than 20%).

The focus of the project is on materials analysis with THz radiation and related instrumental development. The goal is to expand the application field of THz ellipsometry and the optical Hall effect towards EPR ellipsometry. The method shall be applied mainly in materials science, particularly for investigations of defects in semiconductors.

The work for the candidate area comprises: 

1) Design and perform THz-EPR ellipsometry experiments, data evaluation and model development for various semiconductor nano- and heterostructures and electronic defects therein.

2) Being involved in the instrument development including hard- and software and integration of new components based on the existing THz ellipsometer.

Additional characterization methods as infrared and vis-UV ellipsometry, electrical Hall effect measurements, and others may be carried out. The work does also include theoretical aspects on anisotropic crystal optics and properties of electron spins. 

Supervisors for the PhD work will be Vanya Darakchieva and Steffen Richter from the  Division of Solid State Physics. Vanya Darakchieva is professor in materials science at the Division of Solid State Physics in Lund, and has long experience in the development of semiconductor material and components from growth to characterization, including applications of THz ellipsometry. Steffen Richter is researcher at the division and has a extensive experience in applications of polarization optics and development of different kinds of ellipsometry at different institutions.

The applicant is expected to work independently as well as in close cooperation with other researchers involved in the project.

Admission requirements

A person meets the general admission requirements for third-cycle courses and study programmes if he or she:

• has been awarded a second-cycle qualification, or
• has satisfied the requirements for courses comprising at least 240 credits of which at least 60 credits were awarded in the second cycle, or
• has acquired substantially equivalent knowledge in some other way in Sweden or abroad.

A person meets the specific admission requirements for third-cycle studies in Physics if he or she has:

• at least 30 second-cycle credits of relevance to the subject, of which at least 15 credits shall comprise a second-cycle degree project, or
• an MSc in engineering physics or an associated field, or a Master’s degree in physics or an associated field.

Finally, the student must be judged to have the potential to complete the programme.

Additional requirements:

• Very good oral and written proficiency in English.

Assessment Criteria

Selection to postgraduate studies is based on the expected ability to perform well in the studies. The evaluation of the ability to perform well is based primarily on the results of studies at the basic and advanced levels, in particular:

1. Knowledge and skills relevant to the thesis project and the subject of the study, see description of Work duties. These can be demonstrated by attached documents.
2. An assessment of ability to work independently and to formulate and tackle scientific research problems. The assessment may be based, for example, on the thesis and a discussion of the thesis during a possible interview.
3. Written and oral communication skills.
4. Other experience relevant to postgraduate studies, such as professional experience.

Other assessment criteria:

• Very good knowledge of semiconductors and crystal optics is expected. Studied courses should include semiconductors and optics.
• Being able to quickly assimilate new techniques and knowledge is an advantage.
• Experience in prototyping including soft- and hardware development is beneficial.
• Experience with ellipsometry/polarization optics or electron-spin-resonance spectroscopy is extra meriting.

Consideration will also be given to good collaborative skills, drive and independence, and how the applicant, through his or her experience and skills, is deemed to have the abilities necessary for successfully completing the third cycle programme.

Terms of employment

Only those admitted to third cycle studies may be appointed to a doctoral studentship. Third cycle studies consist of full-time studies for 4 years. In the case of teaching and other departmental work, the appointment is extended by a corresponding amount, up to a maximum of 5 years (i.e. a maximum of 20%). Employment as a doctoral student is regulated in the Higher Education Ordinance (1993:100), Chapter 5, Sections 1-7.

Instructions on how to apply

Applications must be written in English and include a cover letter stating the reasons why you are interested in the position and in what way the research project corresponds to your interests and educational background. The application must also contain a CV, degree certificate or equivalent, and other documents you wish to be considered (grade transcripts, contact information for your references, letters of recommendation, etc.).

The applicant is also required to answer the job specific questions when submitting the application.

The English version of this announcement is an interpretation of national formalities expressed in the Swedish text. In case of uncertainties, the Swedish text applies.