Are you a eager to build state-of-the-art experiments and use them to explore quantum physics in a lively, international group?
Our
Strontium Quantum Gases Group is looking for ambitious PhD students who want to participate in exciting quantum simulation, sensing and computing experiments. This group is headed by Prof. Florian Schreck and is part of the
Quantum Gases & Quantum Information (QG&QI) cluster at the
Institute of Physics (IoP) of the
University of Amsterdam (UvA) and also hosts the
Quantum Delta NL Ultracold Quantum Sensing Testbed. We use ultracold Sr gases for quantum sensing, to study many-body quantum physics and for quantum computing. We have three open PhD positions, one each on the research projects described below. For more information about the projects take a look at
our website or contact
Florian Schreck.
Project 1: Continuous atom laserIn this project you will build the first continuous atom laser. An atom laser is a beam of atoms that is described by a coherent matter wave. So far only short atom laser pulses have been created by outcoupling a beam of atoms from a Bose-Einstein condensate (BEC). The laser stops working when all atoms of the BEC have been outcoupled, requiring the creation of a new BEC for the next atom laser pulse. BEC creation is usually a lengthy process, requiring several cooling stages to be executed one after the other in time. We have built a machine that can execute these stages one after the other in space, enabling us to Bose-Einstein condense continuously [1]. This allows us to create a BEC that lasts as long as we want. It's the atomic equivalent of an optical laser with perfectly reflective cavity mirrors. Your goal will be to take the next step and outcouple the first continuous atom laser beam from the BEC. Such a beam would be an ideal source for continuous atom interferometry [2]. A second goal of the project is to create interesting driven-dissipative quantum systems and study their properties.
Project 2: Sr optical clocksIn this project you will build an optical clock based on continuous readout of the Sr clock transition. The clock will exploit our continuous ultracold Sr source technology [1] to prepare large samples of ultracold atoms without losing track of time while preparing those samples. This will enable to reach high clock precision after short averaging times, which is important to improve clock stability and for many clock applications. We are pursuing two approaches to achieve this goal: superradiant lasing and zero-deadtime clocks and you could join either one of these research efforts. You will be involved in every aspect of building your clock, from electronics, over lasers, optics, frequency combs, ultrastable resonators to vacuum chambers. Once the clock is operational you will use it to collaborate with other research teams, comparing zero-deadtime and superradiant clocks, enabling precise qubit operations in our quantum computer (project 3), or studying fundamental physics with precision spectroscopy (with our colleagues at the Free University). For the latter you will participate in setting up a frequency link through telecom fibres to the Free University in Amsterdam and to the Eindhoven University of Technology. This project is part of the Quantum Delta NL Ultracold Quantum Sensing Testbed, which will give you many opportunities to work with industry, in particular to design photonic circuits for optical clocks.
Project 3: Quantum simulation and computing with Rydberg coupled single Sr atomsQuantum computers and simulators can solve problems that are utterly out of reach for traditional computers. We are building two quantum computers/simulators based on arrays of strontium atoms held in optical tweezers [4], one in our lab and one at the Eindhoven University of Technology. Quantum bits are encoded in the internal states of these atoms and quantum calculations are carried out by shining laser beams onto the atoms in a well-orchestrated way. Quantum computers based on neutral atoms profit from the fact that the atoms are naturally identical and that it is quite easy to scale the computer to hundreds of quantum bits. Our quantum computer is based on strontium atoms, an alkaline-earth element that is also commonly used to build some of the best clocks in the world. Exploiting the clock built in project 2 and supported by
QuantumDelta NL and the
Quantum Software Consortium we are building quantum computers that can demonstrate algorithms developed by
QuSoft or solve quantum chemistry problems. In Amsterdam we can currently trap strontium atoms in an array of 49 tweezers [5]. You will extend this machine with the lasers necessary to implement one- and two-qubit gates and perform quantum simulations and computations with it.
References
- Chun-Chia Chen (陳俊嘉), Rodrigo González Escudero, Jiří Minář, Benjamin Pasquiou, Shayne Bennetts, Florian Schreck, Continuous Bose-Einstein condensation, Nature 606, 683 (2022).
- N. P. Robins, P. A. Altin, J. E. Debs, and J. D. Close, Atom lasers: production, properties and prospects for precision inertial measurement, Phys. Rep. 529, 265 (2013).
- Andrew D. Ludlow, Martin M. Boyd, Jun Ye, E. Peik, and P. O. Schmidt, Optical atomic clocks, Rev. Mod. Phys. 87, 637 (2015).
- M. Morgado, S. Whitlock, Quantum simulation and computing with Rydberg-interacting qubits, AVS Quantum Sci. 3, 023501 (2021).
- Alexander Urech, Ivo H. A. Knottnerus, Robert J. C. Spreeuw, Florian Schreck, Narrow-line imaging of single strontium atoms in shallow optical tweezers, Phys. Rev. Research 4, 023245 (2022).
Tasks and responsibilities:
- Designing, constructing and debugging ultracold atom experiments;
- conducting research, resulting in academic publications in peer-reviewed international journals and/or books;
- supervising Bachelor and Master theses and tutoring students;