Electron microscopes have long served as an indispensable window into the microscopic universe, revealing cellular structures, nanoscale materials, and complex molecular formations far smaller than anything visible with ordinary light. Yet, despite their extraordinary capabilities, researchers in Austria say that conventional electron microscopes may be leaving valuable information on the table.
In a standard electron microscopy system, electrons are primarily counted to build a visual image of a sample. However, physicists point out that each individual electron also carries rich quantum information that normally goes completely unused during the imaging process. To address this limitation, an interdisciplinary team of researchers at TU Wien, working in close collaboration with teams from the University of Vienna, JKU Linz, and the University of Innsbruck, has developed a groundbreaking new approach designed to capture, harness, and process that extra layer of quantum information.
The core concept of their innovative research is to physically connect an advanced electron microscope directly to a quantum computer. By bridging these two distinct technologies, the researchers hope to extract significantly more useful data from each passing electron. This technical leap could potentially allow scientists to form much clearer, higher-resolution images while exposing delicate, radiation-sensitive samples to a drastically lower number of electrons. Such a breakthrough could prove especially valuable for examining fragile biological materials, such as individual proteins, which are notoriously easily damaged by standard high-intensity electron beams. A prototype quantum computer electron microscope based on this ambitious concept is now actively being constructed at TU Wien.
Using Quantum Entanglement to Get More From Each Electron
Modern electron microscopes already achieve extraordinary resolution, allowing researchers to peer deep into the atomic scale. However, unlocking these high-resolution images carries a steep physical cost.
"Today, we can image tiny details on the atomic scale," says Philipp Haslinger from the Institute of Atomic and Subatomic Physics at TU Wien. "然而, this requires a large number of electrons. And not every sample can be exposed to so many electrons without being damaged. This is often a problem, particularly when imaging biological samples such as individual proteins."
Because biological specimens and other delicate nanostructures degrade rapidly under sustained particle bombardment, the primary challenge facing modern microscopy is figuring out how to learn more from each individual electron. If scientists can successfully extract more diagnostic value from every single particle that interacts with a sample, they can drastically reduce the total number of electrons needed to produce a clear, high-contrast image.
The interdisciplinary research team proposes solving this fundamental dilemma by linking the microscope’s electron beam directly to a specialized quantum computer built around trapped ions.
"Our idea is to combine the electrons with a quantum computer. We let them interact with ions that are held in place along the path of the electron beam," explains Elias Pescoller, the first author of the scientific publication and a doctoral student at the Institute for Theoretical Physics and the Institute of Atomic and Subatomic Physics at TU Wien. "This can, for example, create quantum entanglement between the electron and the quantum computer. The electron and the ion then share a joint quantum state."
In the realm of quantum mechanics, quantum entanglement is a phenomenon that allows two distinct quantum systems to share physical information in ways that have no direct equivalent in classical physics. Within this novel experimental setup, an electron passing through the microscope column can become quantum-mechanically entangled with a trapped ion inside the integrated quantum computer. This delicate interaction allows precise information about the electron’s journey and properties to be stored securely within the ion rather than being permanently lost to the surrounding environment.
Turning Weak Signals Into Useful Information
The mechanics of the proposed system extend far beyond a single interaction. After one electron interacts with the trapped ion, a subsequent electron can pass through the system and become entangled with the quantum computer as well. By repeatedly carrying out carefully designed, synchronized quantum operations, the integrated system can effectively combine and synthesize information gathered from multiple electrons over the course of an exposure.
"If we perform very specific quantum-computing operations each time, we can optimally combine the information from several electrons so that we obtain a signal of maximum strength even though we use only a relatively small number of electrons," notes Dennis Rätzel from the Institute of Atomic and Subatomic Physics at TU Wien.
The complex mathematical algorithms and protocols needed to carry out this sophisticated data processing were developed in close collaboration with Johannes Kofler’s research team at JKU Linz.
Despite the integration of quantum computing hardware and advanced algorithms, the foundational imaging process remains rooted in traditional physics. The basic imaging process still relies on physical electrons to probe the sample, just as it does in any conventional electron microscope. The fundamental difference lies entirely in the fact that the quantum computer can capture, retain, and process the subtle quantum information carried by those electrons that would otherwise be entirely lost during standard detection.
"The electrons themselves are used to image small objects, just as in any other electron microscope. But by processing the quantum information carried by these electrons in a quantum computer, we can extract significantly more information from the process," says Iva Březinová from the Institute for Theoretical Physics at TU Wien. "What would previously have been indistinguishable from random noise can thus become a clear signal."
By transforming what was once discarded background noise into coherent, interpretable data, the technique could allow scientists to recover critical structural details that would otherwise be completely impossible to identify using ordinary electron counting alone.
"Quantum physics allows us to overcome the statistical limits that constrain conventional electron microscopes," adds Elias Pescoller, emphasizing the theoretical power of the new methodology.
From Mathematical Proof to a Working Microscope
Up to this point, the international research collaboration has successfully demonstrated mathematically that the proposed method should offer substantial practical advantages over traditional imaging techniques. The next major hurdle for the team is to transition from theoretical models to physical reality by demonstrating those benefits experimentally in a laboratory setting.
At TU Wien’s University Service Center for Transmission Electron Microscopy (USTEM), researchers are already preparing the physical infrastructure required to integrate an ion-based quantum computer directly into an operating electron microscope. The sophisticated quantum computing hardware itself was developed by Philipp Schindler’s specialized team at the University of Innsbruck.
If the hybrid system performs as expected during upcoming experimental trials, it could fundamentally open a brand-new approach to electron microscopy. In this envisioned future, researchers would be able to gain vastly superior structural information while exposing sensitive, radiation-vulnerable samples to significantly fewer electrons, preserving specimens that were previously too delicate to image effectively.
"It is really exciting that, within the quantA Cluster of Excellence, we can combine the expertise in quantum information, quantum computing and electron microscopy available at the different universities in Austria. This allows us to launch a unique project," says Thomas Juffmann from the University of Vienna, highlighting the collaborative spirit driving the research forward.
Major funding and institutional support for the multi-institution consortium, which is coordinated by the University of Vienna, comes primarily from the Austrian Science Fund through the Cluster of Excellence quantA, alongside substantial contributions from the Gordon and Betty Moore Foundation.
