ETH News

Researchers at ETH Zurich have studied topological effects in an artificial solid, making surprising observations. The new insights into topological pumping could be used for quantum technologies in the future.

Researchers at ETH have managed to trap ions using static electric and magnetic fields and to perform quantum operations on them. In the future such traps could be used to realize quantum computers with far more quantum bits than have been possible up to now.

Researchers at Empa and ETH Zurich have developed methods for making perovskite quantum dots faster and more efficient emitters, thereby significantly improving their brightness. This is relevant for applications in displays as well as in quantum technologies.

ETH Zurich researchers have detected a new type of magnetism in an artificially produced material. The material becomes ferromagnetic through minimization of the kinetic energy of its electrons.

ETH Zurich is participating in two quantum computing projects that are being financed by IARPA, the US research funding agency, with up to 40 million dollars. Both projects aim to connect two error-corrected qubits with one another and thus lay the foundation for future quantum computers.

Quantum mechanics describes the forces that hold the world together on the smallest scale. The theory of relativity explains the world at the cosmic level. The two seem incompatible – and a unifying theory is nowhere in sight.

Researchers at ETH have created an antenna for light sources on a chip using an unusual placement of a semiconductor material. In the future, efficient nanoscale LEDs and lasers could be produced in this way.

John von Neumann was one of the most important mathematicians and computer pioneers of the 20th century – and an ETH alumnus. He began his studies in chemistry here one hundred years ago. ETH Professor Benjamin Sudakov pays tribute to a mathematical legacy at a symposium.

In theory, quantum computers vastly outperform classical computers in terms of computing speed. For them to do so in practice, it is necessary to design more and novel high-speed algorithms, says ETH supercomputing specialist Torsten Hoefler.  

ETH Zurich researchers have succeeded in demonstrating that quantum mechanical objects that are far apart can be much more strongly correlated with each other than is possible in conventional systems. For this experiment, they used superconducting circuits for the first time.

Researchers at ETH Zurich have created the heaviest Schrödinger cat to date by putting a crystal in a superposition of two oscillation states. Their results could lead to more robust quantum bits and help to explain why quantum superpositions are not observed in everyday life.

Around the world, the race is on to achieve a decisive breakthrough in quantum research. ETH Zurich is spearheading its own challenge.

A special year is soon coming to an end. In 2022, much has been researched, developed and invented at ETH Zurich. ETH News looks back on an eventful past year.

ETH Professor Klaus Ensslin spent 12 years at the helm of the National Centre of Competence in Research “Quantum Science and Technology”. As the programme prepares to wind down at the end of this year, we spoke to him about scientific breakthroughs and Switzerland’s role in quantum research.

For the first time, ETH Zurich researchers have been able to make a superconducting component from graphene that is quantum coherent and sensitive to magnetic fields. This step opens up interesting prospects for fundamental research.

The Swiss National Science Foundation has awarded Advanced Grants to make up for the loss of European support. Researchers at ETH Zurich did particularly well, with 6 of the 24 grants going to the university.

What the “Night of Physics” really aims to do is make physics accessible to a broad audience in a way that’s entertaining. This event will be held on 17 June. Klaus Ensslin, Professor of Physics and co-initiator of the event, explains why it’s worth coming along to the Hönggerberg campus.

Researchers at ETH Zurich have succeeded for the first time in trapping excitons - quasiparticles consisting of negatively charged electrons and positively charged holes – in a semiconductor material using controllable electric fields. The new technique is important for creating single photon sources as well as for basic research.  

"Where the future begins" is the name of ETH Zurich's new image film. Based on six projects, it provides a look behind the scenes and highlights how ETH Zurich is tackling the big questions. The new film was produced by Seed, the same agency that realised the successful ETH trailer "Ready?" five years ago.

Researchers at ETH Zurich have succeeded, for the first time, in quickly and continuously correcting errors in digital quantum systems. This means they have overcome an important hurdle on the road to practical quantum computing.

Matteo Fadel is investigating the interplay between quantum mechanics and gravity as part of his Branco Weiss Fellowship. He wants to observe quantised sound waves with the help of a sapphire.

Two years ago, ETH launched the innovative Master’s degree in quantum engineering. Now the first cohort of students is nearing the end of the programme.

Could quantum technologies really be the next gold rush? ETH Vice President Vanessa Wood and quantum researcher Andreas Wallraff discuss how close we are to putting quantum promises into practice.

Quantum physics opens our eyes to the holistic nature of reality. Nothing can be observed in isolation – and everything is governed by chance.

For a long time, the development of quantum computers was concerned with theoretical and hardware aspects. But as the focus shifts towards programming, software and security issues, the classical computer sciences are coming back into play.

If only it were less prone to error, quantum physics might already be giving us instant solutions to seemingly unsolvable problems. ETH researchers are therefore working to develop systems that are more robust.

At ETH Zurich researchers have observed a new state of matter: in graphene layers twisted relative to each other, two electrical conductors team up to form an insulator.

Some physical systems, especially in the quantum world, do not reach a stable equilibrium even after a long time. An ETH researcher has now found an elegant explanation for this phenomenon.

Researchers at ETH Zurich have trapped a tiny sphere measuring a hundred nanometres using laser light and slowed down its motion to the lowest quantum mechanical state. Based on this, one can study quantum effects in macroscopic objects and build extremely sensitive sensors.

The more connected the world becomes, the greater the demands that data traffic places on communications infrastructure. ETH Pioneer Fellow Marc Reig Escalé and his team develop innovative chips that process information faster than previously possible while requiring even less energy.

Researchers at ETH Zurich have succeeded in observing a crystal that consists only of electrons. Such Wigner crystals were already predicted almost ninety years ago but could only now be observed directly in a semiconductor material.

The future quantum computers should be capable of super-fast and reliable computation. Today, this is still a major challenge. Now, computer scientists led by ETH Zurich conduct an early exploration for reliable quantum machine learning.

ETH Zurich and the Paul Scherrer Institute (PSI) establish a joint centre for the development of quantum computers. Its aim is to advance the realization of quantum computers based on both ion traps and superconducting components. ETH Zurich provides 32 million francs for this centre, which will host around 30 researchers.  

An extraordinary year is drawing to a close. ETH News takes a look back at the highlights that emerged amidst difficult and unsettling times, at ingenious ideas, fascinating science and solidarity in action during – and despite – the coronavirus pandemic.

Quantum research has long since ceased to be an exclusive domain of physics. The purpose of the new ETH Quantum Center is to ensure ETH Zurich’s various competences and activities in this area are networked even more closely and to raise their public profile.

ETH Zurich intends to further expand its leading position in quantum research, and so it is planning a highly specialised physics laboratory building on the Hönggerberg campus. A generous donation from ETH alumnus and ETH Honorary Councillor Martin Haefner is now the key step to taking the project further.

Two research projects with ETH Zurich involvement have been awarded one of the highly coveted ERC Synergy Grants. These EU grants aim to promote pioneering research that is only possible through the synergy of several teams. More than EUR 26 million will now be made available for the two projects.

Researchers at ETH have demonstrated a new technique for carrying out sensitive quantum operations on atoms. In this technique, the control laser light is delivered directly inside a chip. This should make it possible to build large-scale quantum computers based on trapped atoms.

Celeste Carruth originally planned to be a musician. Now she is a physicist at ETH working to develop a new technique for controlling ions. As a member of the WEF’s Young Scientist community, she wants to help non-scientists better understand quantum physics.

Several technical advances have been achieved recently in the pursuit of powerful quantum computers. Now, Computer scientists from ETH Zurich have made an important breakthrough in the field of programming languages: their quantum language is the first of its kind that is as elegant, simple and safe as classical computer languages.

In a material made of two thin crystal layers that are slightly twisted with respect to each other, researchers at ETH have studied the behaviour of strongly interacting electrons. Doing so, they found a number of surprising properties.

Remote research, what does that mean? Andreas Wallraff is currently running the Quantum Device Lab from home.

How is teaching at ETH dealing with the explosion of information in research and technology? Besides developing specialist knowledge, teaching is increasingly concerned with interdisciplinary skills such as critical thinking and the ability to filter, understand and apply relevant information.

Physicists at ETH Zurich have demonstrated a five-metre-long microwave quantum link, the longest of its kind to date. It can be used both for future quantum computer networks and for experiments in basic quantum physics research.

Physicists at ETH Zurich have observed a surprising twist in a quantum system caused by the interplay between energy dissipation and coherent quantum dynamics. To explain it, they found a concrete analogy to mechanics.

Quantum mechanics is a well-established theory, but at a macroscopic level it leads to intractable contradictions. Now ETH physicists are proposing to resolve the problem with the aid of neural networks.

Switching light beams quickly is important in many technological applications. Researchers at ETH have now developed an “electro-opto-mechanical” switch for light beams that is considerably smaller and faster than current models. This is relevant for applications such as self-driving cars and optical quantum technologies.

At the sixth Times Higher Education (THE) World Academic Summit, experts from the research community and higher education explored and reflected on how digitalisation is changing higher education and on nurturing of talent. ETH Zurich hosted the conference.

In the second round of ETH+, the Executive Board’s funding instrument for new research ideas and exchange between disciplines and departments, five new initiatives were selected. These address a range of topics, from living materials to quantum science.

Are there limits to what computers are actually able to compute, and do quantum computers really solve more problems than conventional computers? Computer scientist Scott Aaronson will discuss these kinds of fundamental questions during the Paul Bernays Lectures 2019.

Time is a fundamental dimension of human existence and comes in many forms. Using a comparative approach, philosopher and physicist Norman Sieroka looks at what distinguishes them, using time travel and music.

In recent decades, NMR spectroscopy has made it possible to capture the spatial structure of chemical and biochemical molecules. Now researchers at ETH have found a way to apply this measurement principle to individual atoms.

In quantum physics the vacuum is not empty, but rather steeped in tiny fluctuations of the electromagnetic field. Until recently it was impossible to study those vacuum fluctuations directly. Researchers at ETH Zurich have developed a method that allows them to characterize the fluctuations in detail.

Researchers at ETH Zurich have used trapped calcium ions to demonstrate a new method for making quantum computers immune to errors. To do so, they created a periodic oscillatory state of an ion that circumvents the usual limits to measurement accuracy.

Light particles normally do not «feel» each other because there is no interaction acting between them. Researchers at ETH have now succeeded in manipulating photons inside a semiconductor material in such a way as to make them repel each other nevertheless.

ETH technology that flew to Mars, rubber duckies that travelled around Duckietown in self-driving taxis and moles that warn of tumours – for ETH, 2018 was marked by innovative flair and extraordinary research. We take a look back.

Three researchers from the ETH Domain, including ETH professor Nicola Spaldin, and a scientist from Stockholm University have received an ERC Synergy Grant of EUR 13.9 million.

Sebastian Krinner is the first winner of the Lopez-Loreta Prize at ETH Zurich. The physicist has a clear goal: he wants to build a quantum computer that is not only powerful, but also works without errors.

The theory of quantum mechanics is well supported by experiments. Now, however, a thought experiment by ETH physicists yields unexpected contradictions. These findings raise some fundamental questions – and they’re polarising experts.

Harvard mathematician Barry Mazur will talk about the unity and scope of mathematics on 11 September in his Paul Bernays Lectures at ETH Zurich. Variety enriches mathematics. This is why it is intriguing to enquire about a unification that combines different mathematical theories and methods.  

To make qubits for quantum computers less susceptible to noise, the spin of an electron or some other particle is preferentially used. Researchers at ETH Zurich have now developed a method that makes it possible to couple such a spin qubit strongly to microwave photons.

In the new quantum information technologies, fragile quantum states have to be transferred between distant quantum bits. Researchers at ETH have now realized such a quantum transmission between two solid-state qubits at the push of a button.

ETH physicists have developed a quantum cascade laser that can be used to visualise weak infrared signals from space. It is now being put to use on a flight of the world’s largest airborne observatory.

Nowadays, it is accepted among physicists that Albert Einstein was wrong in his scepticism of quantum mechanics. This was also confirmed by the Big Bell Test involving over 100,000 people around the world in November 2016.

Plants can convert sunlight into chemical energy with a high degree of efficiency. How this is achieved is still not entirely clear. ETH physicists have now constructed a quantum physical model that aims to answer this question.

An international collaboration led by ETH physicists has used machine learning to teach a computer how to predict the outcomes of quantum experiments. The results could prove to be essential for testing future quantum computers.

ETH physicists have developed a silicon wafer that behaves like a topological insulator when stimulated using ultrasound. They have thereby succeeded in turning an abstract theoretical concept into a macroscopic product.

A type of quantum dot that has been intensively studied in recent years can reproduce light in every colour and is very bright. An international research team that includes scientists from ETH Zurich has now discovered why this is the case. The quantum dots could someday be used in light-emitting diodes.

When symmetries in quantum systems are spontaneously broken, the collective excitation modes change in characteristic ways. Researchers at ETH have now directly observed such Goldstone and Higgs modes for the first time.

Physicist Laura Corman is fascinated by the behaviour of electrons in solids. But this up and coming researcher’s other interests give her plenty of opportunities to get out of the lab.

What do the smallest particles locked up in protons have to tell us about how the universe began and how it will end? This week, physics Nobel laureate David Gross will present three public lectures at ETH Zurich on the theme “A Century of Quantum Physics – from Nuclear Physics to String Theory and Beyond”.

Magnetic data storage has long been considered too slow for use in the working memories of computers. Researchers at ETH have now investigated a technique by which magnetic data writing can be done considerably faster and using less energy.

Science and the IT industry have high hopes for quantum computing, but descriptions of possible applications tend to be vague. Researchers at ETH Zurich have now come up with a concrete example that demonstrates what quantum computers will actually be able to achieve in the future.

Sensitive sensors must be isolated from their environment as much as possible to avoid disturbances. Scientists at ETH Zurich have now demonstrated how to remove from and add elementary charges to a nanosphere that can be used for measuring extremely weak forces.

Lavinia Heisenberg is a theoretical physicist. She is reluctant to accept that General Relativity can be used to describe the universe only on the assumption of exotic materials and energy sources. Her goal is thus to update Einstein’s theory.

Accurate measurements of the frequencies of weak electric or magnetic fields are important in many applications. Researchers at ETH Zurich have now developed a procedure whereby a quantum sensor measures the frequency of an oscillating magnetic field with unprecedented accuracy.

Gases in the environment can be spectroscopically probed fast and precisely using so-called dual frequency combs. Researchers at ETH have now developed a method by which such frequency combs can be created much more simply and cheaply than before.

An international team of researchers led by chemists from ETH Zurich have developed a method for depositing single magnetisable atoms onto a surface. This is especially interesting for the development of new miniature data storage devices.

Light particles do not usually react to magnetic fields. Researchers at ETH Zurich have now shown how photons can still be influenced by electric and magnetic fields. In the future that method could be used to create strong artificial magnetic fields for photons.

When matter is cooled to near absolute zero, intriguing phenomena emerge. These include supersolidity, where crystalline structure and frictionless flow occur together. ETH researchers have succeeded in realising this strange state experimentally for the first time.

Theoretical physicists from ETH Zurich deliberately misled intelligent machines, and thus refined the process of machine learning. They created a new method that allows computers to categorise data – even when humans have no idea what this categorisation might look like.

Quantum systems consisting of many particles are a major challenge for physicists, since their behaviour can be determined only with immense computational power. ETH physicists have now discovered an elegant way to simplify the problem.

Three ETH Zurich researchers have received ERC Consolidator Grants from the European Research Council (ERC). Their projects will each receive approximately 2 million Swiss francs in funding.

Quantum mechanics can be entertaining: anyone with a few minutes to spare for a video game on 30 November can do their bit to help solve a fundamental question of physics that was once argued over by Albert Einstein and Nils Bohr. ETH Professor Andreas Wallraff explains what the Big Bell Test is all about.

The ETH Zurich Latsis Prize 2016 goes to ETH physics professor Jonathan Home. He studies the frontier between quantum and classical physics using individual charged atoms that he controls with high precision.

Electrons in a solid can team up to form so-called quasiparticles, which lead to new phenomena. Physicists at ETH in Zurich have now studied previously unidentified quasiparticles in a new class of atomically thin semiconductors. The researchers use their results to correct a prevailing misinterpretation.

The electronic energy states allowed by quantum mechanics determine whether a solid is an insulator or whether it conducts electric current as a metal. Researchers at ETH have now theoretically predicted a novel material whose energy states exhibit a hitherto unknown peculiarity.

Upon application of ETH President Lino Guzzella the ETH Board appointed a total of eight professors and awarded the title of professor to one individual.

For years physicists have strived to control the quantum states of atoms or molecules very accurately. Researchers at ETH Zurich have now established a record for the size of  quantum states generated with massive particles. Their technique could be used to make quantum computers faster.

In phase transitions, for instance between water and water vapour, the motional energy competes with the attractive energy between neighbouring molecules. Physicists at ETH Zurich have now studied quantum phase transitions in which distant particles also influence one another.

Entanglement between distant quantum objects is an important ingredient for future information technologies. Researchers at the ETH have now developed a method with which such states can be created a thousand times faster than before.

Studying peculiar properties of a long known metallic material researchers have chanced upon a new particle. It is related to the so-called Weyl fermions that the mathematician Hermann Weyl predicted almost ninety years ago. Weyl had overlooked the particle, which could have interesting applications in electronics.

Resonators are an important tool in physics. The curved mirrors inside the resonators usually focus light waves that act, for instance, on atoms. Physicists at ETH Zurich have now managed to build a resonator for electrons and to direct the standing waves thus created onto an artificial atom.

French Nobel laureate Serge Haroche will give the Paul Bernays Lectures next week at ETH Zurich. In his research he deals with the transition from quantum physics to classical physics.

Sebastian Huber and his colleagues show that the road from abstract theory to practical applications needn’t always be very long. Their mechanical implementation of a quantum mechanical phenomenon could soon be used for soundproofing purposes.

ETH professor Jonathan Home and his colleagues reach deep into their bag of tricks to create so-called “squeezed Schrödinger cats”. These quantum systems could be extremely useful for future technologies.

Bettina Heim has succeeded in publishing the results of her semester project in one of the most prestigious scientific journals. Heim was able to show why in certain tests current quantum computing devices were no faster than conventional computers, contrary to previous assumptions. ETH News met the former top athlete and now successful scientist.

Jonathan Home’s laboratory has a room full of equipment that traps tiny ions and places them in special quantum states – perhaps the first step towards building a quantum computer.

Two ETH Zurich researchers receive money for their projects from the Swiss National Science Foundation. This will bridge the gap in financing left by the exclusion of Swiss researchers for ERC grants.

In experiments using ultracold atoms and laser light, ETH researchers have measured a stepwise change in conductivity as the atoms pass through tiny structures. This is the first time that this quantum effect has been observed for electrically neutral particles.