Internship Position as Research Assistant in Quantum Technology with Trapped Ions

Fysikum is one of the larger institutions in Sweden within the Faculty of Science, with a broad fundamental research activity, both experimental and theoretical.

The department has about 250 employees, of which 95 are PhD students, and it has an international character. Fysikum is part of the AlbaNova University Center, which is a strong research center that, in addition to Fysikum, also houses the Department of Astronomy, the physics departments at KTH, and the Nordic Institute for Theoretical Physics, Nordita. You can read more about us here: https://www.su.se/fysikum/ (https://www.su.se/fysikum/).

Stockholm University is part of the Stockholm Dual Career Network (SDCN), which supports partners of international recruits with professional events, career-related advice, and by building social networks in their new hometown. You can read more here: https://www.staforum.se/sdcn/ (https://www.staforum.se/sdcn/).

Job Description

We offer a paid full-time internship during the summer in the Quantum Technology group with trapped ions. The research assistant will participate in the optimization of a new experiment aimed at trapping Rydberg ions at cryogenic temperatures.

Trapped ions excited to Rydberg orbitals offer fast interaction between their electronic states via dipole-dipole interaction. In quantum information processing, this interaction enables multi-qubit gates that can be much faster than conventional gates based on motional interaction. However, the time in the Rydberg state is limited by the surrounding blackbody radiation causing double ionization. Therefore, we are developing an ion trap in a cryogenic chamber, which will extend the lifetime of the Rydberg state and enable more complex quantum protocols.

Reliable laser control of the ions' electronic states is crucial for all measurements. A laser with an ultra-narrow linewidth at 674 nm is used for coherent control of two long-lived qubit states, and its phase stability and bandwidth need to be optimized. Additionally, two UV lasers will be delivered from the next laboratory for two-photon transition to the Rydberg state, which poses a challenge in terms of point stability and energy efficiency. Finally, mechanical vibrations in the cryostat must be minimized to keep the ions within the focus of the laser beams.

The research assistant will belong to the Quantum Technology group with trapped ions at Stockholm University, led by Prof. Markus Hennrich, and funded by the Marianne and Marcus Wallenberg Foundation (EDU-WACQT). For more information, see https://qtech.fysik.su.se/ (https://qtech.fysik.su.se/).

The research assistant will be responsible for optimizing one or more aspects of the experiment. For the qubit laser with narrow linewidth, we intend to implement self-injection locking and feedforward filtering. The UV lasers will be delivered via a free-space bridge, and therefore careful beam shaping, control, and loss budgeting will be necessary. Mechanical vibrations can be suppressed by constructing and using a heavy bellows holder placed between the cryostat and the Gifford-McMahon cooler head.

Qualifications

• Ongoing undergraduate education in a field related to physics or optics, with expected graduation no earlier than the end of this temporary employment.
• Good English communication skills.
• Interest in experimental work.

About the Employment

The position is temporary, full-time, intended for 11 weeks during the summer. The timeframe can be adjusted according to the applicant's academic schedule. Stockholm University applies individual salary setting. Start date by agreement.

We Offer

With us, you will experience the dynamics of the interplay between higher education and research, making Stockholm University an exciting and creative environment. You will work in an international setting and receive favorable conditions. The university is located in the National City Park with good connections to the city.

Stockholm University is committed to being a workplace free from discrimination and providing equal rights and opportunities for all.

Contact

Further information is provided by Ivo Straka, phone 08-5537 8088, mailto:ivo.straka@fysik.su.se.

Application

You apply for the position via Stockholm University's recruitment system. As an applicant, you are responsible for ensuring that the application is complete and that it reaches the university no later than the application deadline.

Instructions for applicants can be found on the webpage: https://www.su.se/om-universitetet/jobba-på-su/att-söka-en-anställning (https://www.su.se/om-universitetet/jobba-p%C3%A5-su/att-s%C3%B6ka-en-anst%C3%A4llning).

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