Report

Teaser, summary, work performed and final results

Periodic Reporting for period 1 - Q-SORT (QUANTUM SORTER)

Teaser

Q-SORT is working on a new generation of electron microscopes – so-called ‘Quantum Sorters’, able to probe delicate specimens with extremely low damage. Potential benefits include the ability to determine protein structures that could lead to new drugs for healthcare &...

Summary

Q-SORT is working on a new generation of electron microscopes – so-called ‘Quantum Sorters’, able to probe delicate specimens with extremely low damage. Potential benefits include the ability to determine protein structures that could lead to new drugs for healthcare & next-generation biomedicine.

For decades scientists & the wider public have marvelled at the images produced by e-microscopy. Modern machines can now fire powerful electron beams to produce images with single-atom resolution. But e-microscopes are much more than simple imagers: they can in fact be used to study properties such as the composition of a sample or its magnetic, mechanic, structural, electronic properties. An important issue in e-microscopy is the so-called ‘dose problem’, which causes delicate samples, e.g. proteins, to be damaged or destroyed. This forces scientists to seek an awkward trade-off between resolution & sample integrity. Careful specimen handling is key in important research fields such as biology and biochemistry, that typically feature delicate samples.

Q-SORT is developing radically new techniques to study fragile specimens at the micro level. Q-SORT exploits TEM (transmission electron microscopy), a technique in which electrons are passed through an ultra-thin slice of specimen to form an image. Q-SORT leverages the recently-acquired capacity to structure e-beams, thus turning the TEM into what scientists call a ‘quantum state sorter’ or ‘quantum sorter’. Sorters can probe the properties of samples using very few electrons, allowing scientists to answer tricky questions about the specimens with extremely low damage. The advantage of the sorter stems from the idea of re-thinking the set-up of the TEM in order to optimise the extraction from the sample of a specific quantity of interest. This is achieved through the operation of sorting specific electron quantum states out of the e-beam, after it has interacted with the sample. Knowledge of this decomposition provides useful information.

Applying the Sorter to cryoTEM is especially exciting. CryoTEM is a technique generally used for biological specimens, in which a flash-frozen solution is fed into a TEM. In cryoTEM the Sorter can be used to recognise protein structures & properties. These proteins can be cell-signalling molecules, or parts of membranes, which ultimately provide researchers with knowledge of how cells and tissues function. But the Sorter is a key enabling technology in many other fields: this new paradigm in measurement should allow researchers to map magnetism down to the atomic scale & to investigate various exotic electronic excitations in materials.

Q-SORT’s 4 goals are: to develop tools & techniques for sorting, to apply them to cryoTEM, to magnetic spin properties, to plasmons.

Q-SORT entails a comprehensive outreach & dissemination strategy, centered on a bold mix of online and offline engagement. Its objectives are: to communicate Q-SORT to the wider public, to spread awareness of excellent EU-funded research, to prime public interest in Q-SORT physics, to foster interdisciplinary dialogue between physics and biochemistry. This is especially important for the uptake of project results.

Work performed

During its first year of activity, Q-SORT has achieved all the goals as detailed in the Project Workplan:
1) A completely novel configuration for a working Orbital Angular Momentum Sorter has been designed, built, and tested in the state-of-the-art Titan Holo microscope at Juelich. The OAM Sorter initially made use of holograms to impart the desired phase onto electrons. New electrostatic devices should replace when possible the holograms for the rest of the project. These were designed, built, and tested during the first year. While holograms permit greater flexibility as well as the new advantageous fan-out mode, electrostatic devices guarantee a nearly attenuation- and scatter-free operation.
2) With view to a theory for a general-purpose Sorter, many new ideas for the dose-efficient detection of proteins have been studied. The methods range from genetic-algorithmic hologram optimisation to an evolution of the OAM Sorter and to single-pixel detection.
3) Design work was also carried out for the cryogenic modification of Titan Holo, which as a result will become a completely new instrument, unique in the world, allowing for advanced and innovative experiments.
4) A theoretical effort was undertaken aimed at the calculation of the spectrum of electrons in energy and Orbital Angular Momentum for future experiments on nanoparticle plasmon excitations.
5) Dissemination and communication provided Q-SORT with a distinctive graphic identity and website, then established its online presence over the main social media, then enacted a combination of online & offline engagement activities.

Final results

Very little progress has taken place in state sorting outside Q-SORT. The idea itself has arisen in the last 1÷2 years. Completely new results for Q-SORT so far include the following:
- The OAM Sorter was modified in the so-called fan-out mode, a uniquely advantageous sorting mode.
- Until Q-SORT the electrostatic version of the sorter was only a theoretical model. We improved the theory and design of the e.s. sorter with new solutions to compensate for aberrations.
- We worked on new electrostatic devices & on solutions to introduce these elements in the TEM. Application of MEMS technology to this problem is an original result of Q-SORT. These are cutting-edge innovation/industrial developments.
- As for theory, Q-SORT opened a completely new field: the research for the optimal quantum sorting method, which is among the greatest innovations of the project.
- The methods introduced by Q-SORT for optimal electron detection are absolutely novel. Similar ideas have been used in optics but are completely new in TEM.
- As a preliminary application to plasmon physics, we created a new theoretical model for predicting the results of an OAM Sorter. Current state of the art in the field is devoid of such a model.
- The new hardware designed in this project, integrating cryoblades in a holographic TEM also represents a unicum on a world level and will become the reference point for many new low-dose experiments.
In a sense, Q-SORT aims to surpass the results that led to the 2017 Nobel Prize for Chemistry.

Expected results by the end of Q-SORT include:
a fully working OAM sorter with optimised efficiency;
a general theoretical framework for novel sorting problems;
a generalised sorter for cryoTEM;
its application to the problem of the orientation of protein “hepta pdbid 3J83”, which is of interest in translational research in drugs discovery/vaccinology related to tuberculosis;
a demonstration of atomic-scale characterisation of magnetic states of matter through magnetic dichroism measured via OAM sorting;
the application of the OAM sorter to determine the symmetries of select nanoparticles via analysis of plasmonic modes.

Social impact: Q-SORT addresses H2020 challenges by connecting science to society in new ways:
Opens new avenues for further research & innovation by developing a revolutionary new tool for many applications & establishing a bold interdisciplinary dialogue between physicists & biologists.
Fosters gender equality in science.
Increases the no. of Open Access papers.
Promotes social awareness & responsibility (RRI).
Engages new audiences in science, through innovative participative initiatives.

Website & more info

More info: http://www.qsort.eu.