PhD student in Quantum Information Theory and Quantum Optics

he Department of Physics is located in the AlbaNova University Center and has approximately 240 employees, 250 students at undergraduate level and 90 graduate students. There are four research subjects within the postgraduate program: Physics, Theoretical Physics, Chemical Physics and Medical Radiation Physics. These subjects span over several research groups with different research activities. For information about the Department of Physics, see: www.fysik.su.se/english.

Project description
Subject: Theoretical Physics

We welcome applications for a PhD position in quantum information theory and quantum optics at Fysikum at Stockholm University. Quantum information theory provides a framework for describing and quantifying genuinely quantum phenomena, such as coherence and entanglement. This theory has been instrumental in modelling a wide array of quantum systems and platforms, facilitating the development of powerful quantum technologies. Nevertheless, many fundamental questions remain unanswered, including the mechanisms driving the quantum-to-classical transition and the nature of the gravitational field generated by a superposed quantum system. A promising approach to addressing these questions involves studying quantum systems with masses significantly larger than those of single atoms. These systems can often be described as mechanical resonators in the quantum regime, with examples ranging from levitated silica or diamond nanoparticles to clamped membranes and microscopic mirrors. When coupled to a probe field, these systems can be measured and controlled with high precision, an area of research known as quantum optomechanics.

Our ability to model mechanical resonators in the quantum regime is advancing rapidly. Theoretical models that incorporate environmental noise and state preparation have led to groundbreaking developments, such as ground-state cooling and the creation of superposed and entangled states involving billions of atoms simultaneously. The relatively large size and mass of these systems also leave them highly sensitive to weak effects, making them exceptional quantum-enhanced sensors. The primary objective of this PhD project is to investigate massive quantum systems through concepts and methods from quantum information theory and quantum optics. Key areas of focus include modelling the fundamental interactions between these systems and other probes or environments, as well as developing open-system dynamics and methodologies geared towards experimental applications. Future research directions may involve exploring the potential of these systems for quantum sensing and tests of fundamental physics.

The PhD project will be carried out in the research group of Sofia Qvarfort, who is part of the Wallenberg Initiative on Networks and Quantum Information at Nordita. The PhD candidate will be formally enrolled at Stockholm University, but is expected to spend their time at Nordita.  We are looking for a motivated and collaboration-oriented candidate with excellent fluency in written and spoken English. Previous knowledge of quantum information theory and quantum optics is a merit. Programme for physics research in e.g. python or Mathematica is a plus. The position comes with the potential to travel and present your work at international conferences, and you will be encouraged to develop your teaching and/or public communication skills.

Education at the research level
A PhD education at Stockholm University is four years (48 months). The 4-year PhD program includes at least 3 years of research and at most one year of course work. The position may be extended by up to one year if up to 20 % teaching assistance or administration is included in the contract. The PhD student is employed (“doktorandanställning”) during the studies, with a monthly salary starting at SEK 30 300.

Qualification requirements

In order to be admitted to postgraduate education, the applicant must have the general and specific entry requirements. The qualification requirements must be met by the deadline for applications.

You meet general entry requirements if you have completed a second-cycle degree, or completed courses equivalent to at least 240 higher education credits, of which 60 credits must be in the second cycle, or have otherwise acquired equivalent knowledge in Sweden or elsewhere.

In order to be accepted as a PhD student in Physics or Theoretical Physics a BSc in Physics (or equivalent) is required. The studies must include 60 credits of second-cycle courses in physics out of which at least 15 credits correspond to a second-cycle degree project. The degree project does not have to have been examined at the application deadline, but work corresponding to half a semester of full-time studies should have been devoted to it. For the subject Chemical Physics courses in chemistry may replace the required physics courses. The subject Medical Radiation Physics requires a second-cycle degree project of 30 credits in the subject area, or with 60 credits of physics, a second-cycle degree project of 30 credits in another subject area.

In addition, proficiency in English language, equivalent to English B in Swedish high school, is required, or

• Previously completed University degree taught in English
• IELTS score (Academic) of 6.0 or more (with none of the sections scoring less than 5.0)
• TOEFL score of 550 or more (computer based test 213, internet based 79)
• Cambridge/Oxford – Advanced or Proficiency level.

Selection
The selection among the eligible candidates will be based on their capacity to benefit from the training. The successful applicant will be selected based on documented theoretical and experimental knowledge relevant for the area of study, knowledge of scientific theory and method, analytical skills, personal motivation and team working skills. Well-developed English language skills are required. The applicants are encouraged to provide supporting documents that substantiate qualifications, e.g., knowledge, skills, abilities and experience.

References and interviews will be used to assess qualifications of the applicants. We seek a self-motivated candidate with good analytical abilities and skilled in English.

Admission Regulations for Doctoral Studies at Stockholm University are available at: www.su.se/rules and regulations.

About the post
We offer a fixed-term employment as a doctoral student according to Chapter 5 of the Higher Education Ordinance (1993:100). The period of employment may not be longer than what corresponds to full-time doctoral education for four years. As a doctoral student, you should primarily devote yourself to your own doctoral education, but the employment may include work with education, research and administration to a limited extent (maximum 20 %).

A new employment as a doctoral student is for a maximum of one year, the employment is then renewed for a maximum of two years at a time.

Stockholm University strives to be a workplace free from discrimination and with equal opportunities for all.

Contact
For more information about the project, please contact Ass. Prof. Sofia Qvarfort, sofia.qvarfort@fysik.su.se.

For information about the employment Prof. Michael Odelius, odelius@fysik.su.se, who can also forward questions to the PhD student council at Fysikum.

Union representatives
Ingrid Lander (Saco-S), telephone: +46 708 16 26 64, saco@saco.su.se, Alejandra Pizarro Carrasco (Fackförbundet ST/OFR), telephone: +46 8 16 34 89, alejandra@st.su.se, seko@seko.su.se (SEKO), and PhD student representative, studentombud@sus.se.

Application
Apply for the PhD student position at Stockholm University’s recruitment system. It is the responsibility of the applicant to ensure that the application is complete in accordance with the instructions in the advertisement, and that it is submitted before the deadline.

Please include the following information with your application

• Your contact details and personal data
• Your highest degree
• Your language skills
• Contact details for 2–3 references
• Important: Your academic referees should send us recommendation letters no later than the closing date, via e-mail to: FV-2781-24.refletters@fysik.su.se and state in the subject line: SU FV-2781-24 + name of the applicant.

and, in addition, please include the following documents

• Cover letter describing among other things:
  – why you are interested in the field/project described in the advertisement
  – what makes you suitable for the project in question
• CV – degrees and other completed courses, work experience and a list of degree projects/theses
• Degree certificates and grades confirming that you meet the general and specific entry requirements (no more than 6 files)
• Degree projects/theses (no more than 6 files).

The instructions for applicants are available at: How to apply for a position.

You are welcome to apply!

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