Research: qM&M Experiment

Quantum Physics research is conducted in the Quantum Measurement and Manipulation Group (QMMG) at Aarhus University with a theoretical and an experimental division. It's in the QMMG that the potential of producing and manipulating ultracold atoms is explored for a number of main goals.


News from the past year

Paper published in PNAS: Remote optimization of an ultracold atoms experiment by experts and citizen scientists

Our paper on the Alice Challenge and remote optimisation of BECs was finally published in PNAS.

We developed a versatile remote gaming interface that allowed external experts as well as hundreds of citizen scientists all over the world through multiplayer collaboration and in real time to optimize a quantum gas experiment in a lab at Aarhus University. Surprisingly, both teams quickly used the interface to dramatically improve upon the previous best solutions established after months of careful experimental optimization. Comparing domain experts, algorithms and citizen scientists is a first step towards unravelling how humans solve complex, natural science problems.

Read the official press release or the published paper in PNAS.

(14/11 2018)


A new paper on the ArXiv: Spatially-selective magnetometry of ultracold atomic clouds

Check out our new paper on the preprint server: Spatially-selective magnetometry of ultracold atomic clouds, arxiv.org/abs/1811.01798.

We realise two types of high precision magnetometers, using Faraday imaging in a balanced homodyne setting. A novelty of the setup lies in the option to spatially shape the probe light, enabling local detection of one/selection of many atom clouds in a tweezer array. We also discuss how this setup could be used to enhance magnetic field sensitive quantum simulations in our quantum gas microscope experiment.

(6/11 2018)


Carrie joins the group

We are happy to announce that Carrie Ann Weidner will join the experimental team as a postdoctoral researcher for the next two years to come. Previously she did her PhD in the United States under the supervision of Dana Anderson, at JILA in Boulder, Colorado. There she built an atom interferometer in a system of shaken optical lattices. Welcome Carrie!

(6/8 2018)


A new publication in Journal of Physics B: Measurement-enhanced determination of BEC phase transitions

Our paper, Measurement-enhanced determination of BEC phase transitions, is now published in Journal of Physics B. The paper can be found under the following link: https://doi.org/10.1088/1361-6455/aad447.

(6/8 2018)


Jens defends progress report

Our PhD student Jens Schultz Laustsen defended his progress report, Method and systems needed for a Quantum gas microscope, with success. Nils Kjærgaard from the university of Otago, New Zealand came to be an external examiner. Congratulations to Jens, who will now continue working towards the ultimate goal of every PhD student.

(22/6 2018)


Single atom images improved

With the latest progress in the lab on the high resolution imaging, we have been working on cleaning the signal to achieve better signal compared to the background level of noise. The image attached displays some tens of 87Rb atoms, trapped in deep optical lattices, and imaged by capturing fluorescent light emitted when the atoms are exposed to near resonant light.

(19/6 2018)


Single atoms observed, in the shape of a heart

As a result of past several months hard work, we have now achieved a greatly improved signal from single atoms trapped in the optical lattices. Here a heart shaped laser beam is projected into the atomic cloud yielding the atomic heart shape (as also reported on this page in an entry from 1 year ago, on the 31/5 2017). The difference is that now we can easily identify individual atoms, that ate the individual dots present in the image below. This is a big leap towards quality images from our quantum gas microscope.

This is also an opportunity to introduce a colormap for our quantum gas microscope. It goes through four colors, from black to purple to pink to white. Click on the image for an enlarged version.

(25/5 2018)


Revised paper on the ArXiv: Remote optimization of an ultra-cold atoms experiment

A revised edition of our paper on the Alice challenge and remote optimisation of BEC’s, is now available on the ArXiv. The title is: Remote optimization of an ultra-cold atoms experiment by experts and citizen scientists. Please find the pdf here: https://arxiv.org/abs/1709.02230.

(27/3 2018)


Atom clouds moved with the DMD in the lab

We managed recently for the first time in our lab to transport atoms contained in a single atomic tweezer using the dynamic mode of our DMD. We transported a cloud of atoms containing some 100’s of atoms over a distance of 15 µm. In the image attached we see atoms trapped in a 4 by 4 array of optical tweezers, after the corners of the array have been moved outwards by 5 µm.

(15/2 2018)