geneva university phd physics

Dipartimento di Fisica

PhD course in Physics and Nanosciences

The PhD course in Physics and Nanosciences offers opportunities for state-of-the-art research and high-level training in various fields of physics, both from experimental and a theoretical points of view. These research fields include the physics of fundamental interactions , condensed matter physics , biophysics , and astrophysics .

The Doctorate in Physics and Nanosciences is currently coordinated by Prof. Riccardo Ferrando ([email protected]) and is divided into three curricula

• Bio-Nanosciences
• Applied Superconductivity

The research carried out in the framework of the Doctorate is in many cases in collaboration with Italian Research Institutes (INFN, CNR, IIT, INAF).  Many international colaborations are also active.

For more information on research activities visit the dedicated section

XXXIX Cycle

The DQMP is a major center of Swiss research in the field of quantum matter physics. Our researchers are constantly understanding new fundamental properties of matter, seeking new materials for the future, discovering innovative phenomena and developing new experimental techniques.

We focuse on innovative materials with fascinating and often extreme properties, studied with avant-garde methods, both from the experimental and theoretical point of view. These materials are undoubtedly one the cornerstones of the 21st century.

The Department employs approximately 120 people organized in 12 research groups , various shared services, and the administration.

A specialization in quantum matter physics constitutes an ideal entry for professional and academic careers. Our programs provide students with an in-depth education, the opportunity to work on innovative research subjects in a convivial atmosphere and in close collaboration with internationally renowned people.

From phenomenology to theoretical studies via modeling, our teams dissect and prepare matter for its applications. The number of collaborations with industrial partners has grown continuously. We are fostering innovation and working closely with industry to bring new technologies to the market.

The Department of Quantum Matter Physics is very active to make science accessible to all, and to awake the interest of the youngest for science.

Latest news

Dimensionality Revealed

An international research team from Innsbruck and Geneva has, for the first time, probed the dimensional crossover for ultracold quantum matter. In the regime between one and two dimensions, the quantum particles perceive their world as being 1D or 2D depending on the length scale on which they… Read more

MaNEP Summer Internships

MaNEP offers 3rd and 4th year physics students the unique opportunity to work for a month this summer in one of the top research teams affiliated to the MaNEP Network, while receiving a financial support. Since 2004, these internships have successfully encouraged several of the participants to…

Charge Density Waves in Unconventional Metal ScV6Sn6

The scientific community has long been fascinated by the mysterious behavior of charge density waves (CDWs) in certain metals, particularly those based on vanadium in the kagome structure. A recent breakthrough, outlined in the paper titled "Phonon Promoted Charge Density Wave in Topological…

MaNEP SWM 2024

We are glad to announce that the new edition of the MaNEP Swiss Workshop on Materials with Novel Electronic Properties will take place in Les Diablerets from August 14th to 16th, 2024.

Compression may cool

An international research team from Innsbruck and Geneva has developed a new thermometry method to measure temperatures for low-dimensional quantum gases. With this method it was found that compressing a gas may lead to cooling. The results on this counterintuitive phenomenon have just been…

Innovative materials to combat bacteria

A UNIGE team is developing new alloys with bactericidal properties to combat antibiotic-resistant germs.

International Workshop Electrons, Photons and Plasmons 2024

The International Workshop “Electrons, Photons and Plasmons, 2024” will take place in presence on June 10-12 in Nyon, Switzerland.

Research Groups at DQMP

Angle-resolved photoemission

Designer quantum materials

Strongly correlated quantum material

Theory of quantum matter

Nano-optics

Quantum electronics

Ferroelectrics and multiferroics

Theory of flat and strange quantum matter

Scanning probe microscopy and spectroscopy

Applied superconductivity

Quantum light-matter

Oxide interface physics

Quantum materials discovery

Affiliated research groups.

Electric power networks

Research with Neutrons and Muons

Research services.

Crystallography service

Publications highlights.

Mapping orthorhombic domains with geometrical phase analysis in rare-earth nickelate heterostructures

Mundet et al. – APL Mater. 12, 031124 (2024)

Structural study of nickelate based heterostructures

Lucia Varbaro, Bernat Mundet, Subhadeep Bandyopadhyay, Claribel Domínguez, Jennifer Fowlie, Lukas Korosec, Chih-Ying Hsu, Duncan T. L. Alexander, Philippe Ghosez, Jean-Marc Triscone

Varbaro et al. – APL Mater. 12, 031104 (2024)

Chemical Principles of Intrinsic Topological Superconductors

Fabian O. von Rohr

Chem. Mater. 2023

Observation of the orbital inverse Rashba–Edelstein effect

Anas El Hamdi, Jean-Yves Chauleau, Margherita Boselli, Clémentine Thibault, Cosimo Gorini, Alexander Smogunov, Cyrille Barreteau, Stefano Gariglio, Jean-Marc Triscone & Michel Viret

El Hamdi  et al. – Nat. Phys. (2023).

Multiple antiferromagnetic phases and magnetic anisotropy in exfoliated CrBr 3  multilayers

Fengrui Yao, Volodymyr Multian, Zhe Wang, Nicolas Ubrig, Jérémie Teyssier, Fan Wu, Enrico Giannini, Marco Gibertini, Ignacio Gutiérrez-Lezama and Alberto F. Morpurgo

Nature Communications volume 14, 4969 (2023)

Determining spin-orbit coupling in graphene by quasiparticle interference imaging

Lihuan Sun, Louk Rademaker, Diego Mauro, Alessandro Scarfato, Árpád Pásztor, Ignacio Gutiérrez-Lezama, Zhe Wang, Jose Martinez-Castro, Alberto F. Morpurgo, Christoph Renner

Nature Communications 14 1, 3771 (2023)

PhD position

Phd and postdoc positions in scanning probe studies of correlated 2d electron materials, postdoc position, future events, flat club – christian rüegg.

Speakers: Christian Rüegg, PSI/UNIGE

Location: Auditoire Stueckelberg Pizza: 12:00, Start discussion: 12:30

Flat Club – Patrycja Paruch

Speakers: Patrycja Paruch, UNIGE

Flat Club – Anna Seiler

Speakers: Anna Seiler Seiler, ETH

Flat Club – Nicola Marzari

Speakers: Nicola Marzari, EPFL/PSI

Location: At the restaurant O’Les Terrasses Du Lac, Nyon (Switzerland)

2024 Swiss Workshop on Materials with Novel Electronic Properties (SWM)

Location: Les Diablerets, Switzerland

The University of Geneva stands among the best universities in the world, thanks to the quality of its scientific research and educational excellence. The Department of Quantum Matter Physics offers an international and lively environment where students, teachers and researchers work in close collaboration. A wide range of specializations is proposed, with a strong emphasis on novel applications of fundamental physics.

Technology transfer

The Department of Quantum Matter Physics is very involved in transferring technologies from its laboratories to industry, as its research activities in understanding and developing quantum materials and devices have a strong potential for applications.

PhD position

Latest news.

Dimensionality Revealed

An international research team from Innsbruck and Geneva has, for the first time, probed the dimensional crossover for ultracold quantum matter. In the regime between one and two dimensions, the quantum particles perceive their world as being 1D or 2D depending on the length scale on which they…

Compression may cool

An international research team from Innsbruck and Geneva has developed a new thermometry method to measure temperatures for low-dimensional quantum gases. With this method it was found that compressing a gas may lead to cooling. The results on this counterintuitive phenomenon have just been…

A laser light bends the motion of atoms

An international research team explains the microscopic origin of the Hall effect: the study, published in Science, is coordinated by the University of Florence in collaboration with LENS, CNR and the universities of Geneva and Grenoble.Bending the motion of atoms with laser light allowed to solve …

Scrambled supersolids

Supersolids are fluid and solid at the same time. Physicists from Innsbruck and Geneva have for the first time investigated what happens when such a state is brought out of balance. They discovered a soft form of a solid of high interest for science. As the researchers led by Francesca Ferlaino…

Ultracold atoms used to verify 1963 prediction about 1D electrons

Physicists from Rice University and the University of Geneva have verified a key prediction from a 55-year-old theory about one-dimensional electronics that is increasingly relevant thanks to Silicon Valley’s inexorable quest for miniaturization.

The apparent inner calm of quantum materials

Transitions between different phases of matter are part of our day-to-day lives: when water freezes, for example, it passes from liquid to solid state. Some of these transitions may be of a different kind, resulting from so-called topological excitations that force all the particles to act in…

Quantum spins →

Cold atoms →

Book – Quantum Physics in One Dimension

It is of course the brave who succeed in this world, and Thierry Giamarchi does just that with this excellent book, written by an expert for the uninitiated … Giamarchi writes in a refreshingly relaxed style with infectious enthusiasm for his subject, and readily combines formal instruction with physical insight. The result is a serious, pedagogical yet comprehensive guide to the fascinating and important field of one-dimensional quantum systems, for which many a graduate student (and not a few oldies) will be grateful. ― David Logan, Oxford University, Journal of Physics

Latest publications

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• 17 April 2024

CERN’s impact goes way beyond tiny particles

• Nikki Forrester 0

Nikki Forrester is a science journalist based in Davis, West Virginia.

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The Compact Muon Solenoid (CMS) detector enabled the discovery of the Higgs boson at CERN, Europe’s particle-physics lab near Geneva. Credit: Richard Juilliart/AFP via Getty

Roughly 100 metres underground, in a tunnel that crosses the border between Switzerland and France, lies the largest machine ever built. The Large Hadron Collider (LHC) compresses and collides tiny bits of matter to recreate the fundamental particles that appeared just one-trillionth of a second after the Universe was created.

It’s all part of a day’s work at CERN, Europe’s particle-physics laboratory near Geneva, which is home to the LHC. The lab, which celebrates its 70th anniversary this year, continues to attract scientists who are eager to uncover the nature of particles that comprise matter. Along with more than 2,600 staff members and 900 fellows, CERN hosted nearly 12,000 visiting scientists from 82 countries in 2022. According to indexed papers on the Web of Science database, the researchers publish, on average, around 1,000 papers each year that explore the origin of the Universe, antimatter, dark matter, supersymmetry and beyond. And their ranks include eminent scientists such as Tim Berners-Lee, credited with inventing the World Wide Web, and physicist Peter Higgs, who died on 8 April.

Peter Higgs obituary: physicist who predicted boson that explains why particles have mass

“Particle physics is basically exploring back in time,” says Alain Blondel, a particle physicist who has worked at CERN and the University of Geneva in Switzerland. “The science we do, together with cosmology, astrophysics and many other fields, explores how the Universe was born and how it works. These are questions that have fascinated people for generations”.

Discoveries made at CERN, such as the production of antihydrogen and the development of the World Wide Web, have affected not only the scientific world, but society as a whole. Yet, the inaccessibility of CERN to the majority of the public has led to an almost mythical perception of the organization, says Andri Pol, a photographer based in Switzerland. Pol spent two years capturing the inner workings of CERN for his 2014 book Inside CERN . “You jump into another world and you feel like an alien,” he says. “I don’t know anything about physics, chemistry or mathematics. But you feel the creativity. There’s a lot of energy not only in the machines, but also the people.”

Retaining and attracting scientific talent was a key driving force behind the creation of CERN. During and after the Second World War, many scientists fled Europe to pursue careers in the United States. In the early 1950s, a small group of European scientists put forth a proposal to create a physics laboratory to unite scientists throughout Europe. On 29 September 1954, 12 member states signed a convention establishing CERN near Geneva (see ‘CERN’S growth’).

Source: CERN

Part of the decision to build CERN in Switzerland was the country’s central location in Europe and its neutrality during the war. In fact, CERN’s convention states, “The Organization shall have no concern with work for military requirements.”

“CERN has this aspect of science for peace,” says Rainer Wallny, a physicist at the Swiss Federal Institute of Technology (ETH) Zurich who chaired the Swiss Institute of Particle Physics in 2020–21. “You are not doing anything military related; you work for the curiosity.”

Now, CERN is governed by a council of 23 member states that provide financial contributions and make decisions regarding the organization’s activities, budget and programmes. CERN’s projected annual revenue for 2023 was 1.39 billion Swiss francs (US$1.53 billion), all of which it spends.“I think it is a great model for international collaboration,” says Wallny. “It has a lot of facilities available that are beyond the scope of individual user groups. No one has a particle accelerator in their backyard.”

The LHC, which is the most powerful particle accelerator in the world, consists of a 27-kilometre ring of superconducting magnets. Inside, two particle beams shoot trillions of protons towards one another at nearly the speed of light, causing some to collide and transform their energy into new particles. Along with the LHC, CERN has eight other particle accelerators, two decelerators, an antimatter factory and a vast array of engineering and computing infrastructure.

These resources bring together thousands of scientists from around the world to tackle big questions in particle physics. Research efforts at CERN led to the discovery of weak neutral currents in 1973, the W and Z bosons in 1983 and three types of neutrino in 1989 1 – 3 . These findings provided support for the standard model of physics, a theory developed in the 1970s that describes the fundamental particles of the Universe and the four forces that shape their interactions. Then, in July 2012, scientists at CERN found evidence for the last key force in the standard model — the Higgs boson 4 .

“I’m fascinated by the concept of having these large, international collaborations working on a scientific puzzle,” says Lea Caminada, a particle physicist at the University of Zurich and the Paul Scherrer Institute in Villigen, Switzerland. Caminada and her research group develop pixel detectors for the Compact Muon Solenoid (CMS), a particle detector experiment at the LHC that does research on the standard model, dark matter and extra dimensions. “Doing high-energy physics is unique. It’s really the energy frontier, and there is no other facility in the world where you can do this,” she says.

The CMS collaboration involves more than 5,900 physicists, engineers, technicians and students from 259 institutions across 60 countries. The collaboration publishes around 100 papers each year and celebrated its 1,000th publication in November 2020. But organizing and contributing to large-scale projects is no simple feat. “It’s not always easy to work at CERN. It’s very hard to organize experiments this big,” Caminada says. For instance, she explains, everyone involved in the CMS experiment can review manuscript drafts and provide feedback before submission of a paper. “But I think it creates opportunities for people in different countries.”

A fount of knowledge

Thea Klæboe Åarrestad’s first experience at CERN was during an undergraduate internship in July 2012. During the paid programme, she took three weeks of classes, met with fellow physicists and attended lectures from specialists in the field. It also happened to be the year CERN announced the discovery of the Higgs boson. “Peter Higgs was there. The press of the free world was there. People were sleeping in lines outside the main auditorium to catch the speech,” she says.

The Gargamelle chamber at CERN, operational during the 1970s, detected neutrinos. Credit: CERN PhotoLab

Åarrestad went on to earn her PhD from the University of Zurich in 2019, where she worked on the CMS experiment at CERN, and then became a research fellow at CERN from 2019 to 2021. “My daughter was five months old when I started commuting to CERN. I spent eight hours on the train every day,” she says. “My friends questioned whether I could do exactly the same work for a company, and I can honestly say no, I can’t.”

Now, as a particle physicist at ETH Zurich, Åarrestad studies how to use machine learning to improve data collection and analysis methods at CERN. “The environment there is fantastic. You go for a coffee and everyone has ideas and thoughts to discuss. I was always very passionate about physics, and being at CERN just made me even more passionate about it because I shared it with so many others,” she says.

Reverberating impacts

The impact of CERN goes well beyond the smashing together of tiny particles. “Such a vibrant intellectual node radiates out to the universities,” says Wallny. He often sends his graduate students to CERN, where they can gain experience in a large, international setting. “There’s a lot of education happening, and not just in science and engineering. You interact with people from other cultures and learn how to express yourself in English,” he adds.

According to Wallny, lessons from organizing large-scale collaborations at CERN can also be applied to other areas of science, such as quantum computing. “In these large experiments, you have to invent your own governance. You have a bunch of usually quite anarchistic academics who still have to play by some rules. You have to give yourself a constitution and a collaboration board. These approaches can easily be copied in other emerging fields of science,” he says.

Investing in projects such as CERN has benefits for society that expand beyond the bounds of academia. Massimo Florio, an economist at the University of Milan in Italy, calculates the costs and benefits of large-scale research infrastructure projects. In 2018, Florio and his colleagues evaluated how procurement orders from CERN for the production of the LHC affected knowledge production, patent filings, sales and profits for more than 350 supplier companies 5 .

Nature Spotlight: Switzerland

“There is clear evidence that after they got an order from CERN, even 10 years later, it was transformative for them,” says Florio. “Even if you give zero value to the discovery of the Higgs boson, the knowledge generated along the way has immediate benefits to society.”

Over the past 70 years, technologies developed at CERN to tackle technical and computing challenges have been applied throughout the world. Perhaps the most notable is the World Wide Web, which was developed by computer scientist Tim Berners-Lee in 1989 to rapidly share knowledge among scientists. In medicine, the technologies from particle accelerators and detectors are used in positron emission tomography scanners and radiation methods for cancer treatments, such as hadron therapy 6 .

Satisfying curiosity

As CERN embarks on its eighth decade of research, the organization is planning to upgrade its accelerators to add to knowledge about the fundamental particles that make up the Universe. Towards the end of 2025, the LHC will be shut down and upgraded to a high-luminosity LHC over about four years. The upgrades aim to increase the machine’s luminosity tenfold, which would result in a larger number of collisions, allowing scientists to observe new events and rare events, such as those producing a Higgs boson, in more detail. “If we’re ever going to produce new physics, we need a lot of data. And in order to get a lot of data, we need more collisions,” says Åarrestad. She notes that upgrades to the LHC will result in almost quadruple the number of collisions that occur now.

Feasibility studies are also being conducted for the potential development of the Future Collision Collider (FCC), a massive, 91-kilometre particle accelerator 7 . A later phase of the proposed FCC is a hadron collider that could have roughly seven times the collision energy of the LHC. But there are concerns about the costs and environmental impacts of the FCC proposals 8 , as well as particle-physics research more broadly. “There are a lot of humans that would benefit from that money. It costs energy and affects the environment to do fundamental physics,” says Åarrestad. “But I think it is something we should continue in the future despite the cost and the energy consumption, because in the end, as humans, what are we if we’re not curious about where we’re from?”

Furthermore, says Pol, basic research often leads to real-world advances. “Sometimes, something new comes out of basic, theoretical research — one never knows. So, you have to give people who are really skilled a chance to try and find out what makes us what we are,” he says.

That sentiment holds for non-scientists, as well. While working on a contribution to the 2023 book Collisions: Stories from the Science of CERN , Lucy Caldwell, a novelist and playwright based in Ireland, had the opportunity to visit the organization. There, she met several scientists and published a fictional piece on the basis of her experiences. “As humankind, we tend to tell the same stories over and over in different variations,” she says. “Being able to go somewhere like CERN and talk to the scientists right at the cutting edge of knowledge gives you, as a writer, new images, new words and new concepts. It gives you ways to make old stories fresh again and ways to tell new stories. And I think that’s important for all of us.”

Nature 628 , S1-S3 (2024)

doi: https://doi.org/10.1038/d41586-024-01100-w

This article is part of Nature Spotlight: Switzerland , an editorially independent supplement. Advertisers have no influence over the content.

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Bringing the Quantum to the Classical: A Hybrid Simulation of Supernova Neutrinos

By Daniel Heimsoth , Physics PhD student

Simulating quantum systems on classical computers is currently a near-impossible task, as memory and computation time requirements scale exponentially with the size of the system. Quantum computers promise to solve this scalability issue, but there is just one problem: they can’t reliably do that right now because of exorbitant amounts of noise.  

So when UW–Madison physics postdoc Pooja Siwach , former undergrad Katie Harrison BS ‘23, and professor Baha Balantekin wanted to simulate neutrino evolution inside a supernova, they needed to get creative.    

Their focus was on a phenomenon called collective neutrino oscillations, which describes a peculiar type of interaction between neutrinos. Neutrinos are unique among elementary particles in that they change type, or flavor , as they propagate through space. These oscillations between flavors are dictated by the density of neutrinos and other matter in the medium, both of which change from the core to the outer layers of a supernova. Physicists are interested in how the flavor composition of neutrinos evolve in time; this is calculated using a time evolution simulation, one of the most popular calculations currently done on quantum computers.    

Ideally, researchers could calculate each interaction between every possible pair of neutrinos in the system. However, supernovae produce around 10^58 neutrinos, a literally astronomical number. “It’s really complex, it’s very hard to solve on classical computers,” Siwach says. “That’s why we are interested in quantum computing because quantum computers are a natural way to map such problems.”  

This naturalness is due to the “two-level” similarities between quantum computers and neutrino flavors. Qubits are composed of two-level states, and neutrino flavor states are approximated as two levels in most physical systems including supernovae.  

In a paper published in Physical Review D in October, Siwach, Harrison, and Balantekin studied the collective oscillation problem using a quantum-assisted simulator, or QAS, which combines the benefits of the natural mapping of the system onto qubits and classical computers’ strength in solving matrix equations.  

In QAS, the interactions between particles are broken down into a linear combination of products of Pauli matrices, which are the building blocks for quantum computing operations, while the state itself is split into a sum of simpler states. The quantum portion of the problem then boils down to computing products of basis states with each Pauli term in the interaction. These products are then inputted into the oscillation equations.

“Then we get the linear-algebraic equations to solve, and solving such equations on a quantum computer requires a lot of resources,” explains Siwach. “That part we do on classical computers.”   

This approach allows researchers to use the quantum computers only once before the actual time evolution simulation is done on a classical computer, avoiding common pitfalls in quantum calculations such as error accumulation over the length of the simulation due to noisy gates. The authors showed that the QAS results for a four-neutrino system match with a pure classical calculation, showcasing the power of this approach, especially compared to a purely quantum simulation which quickly deviates from the exact solution due to accumulated errors from gates controlling two qubits at the same time.  

Still, as with any current application of quantum computers, there are limitations. “There’s only so much information that we can compute in a reasonable amount of time [on quantum computers],” says Siwach. She also laments the scalability of both the QAS and full quantum simulation. “One more hurdle is scaling to a larger number of neutrinos. If we scale to five or six neutrinos, it will require more qubits and more time, because we have to reduce the time step as well.”  

Harrison, who was an undergraduate physics student at UW–Madison during this project, was supported by a fellowship from the Open Quantum Initiative , a new program to expand undergrad research experiences in quantum computing and quantum information science. She enjoyed her time in the program and thinks that it benefits students looking to get involved in research in the field: “I think it’s really good for students to see what it really means to do research and to see if it’s something that you’re capable of doing or something that you’re interested in.”  

Physics and Astronomy

Graduate Students Successfully Defend Theses

Congratulations to four graduate students in the Department of Physics and Astronomy who successfully defended their doctoral theses in March and April!

The students, listed with thesis title and thesis director, were:

Sanjay Chepuri: "Studying Earth's Magnetosphere with Energetic Particle Observations." Director: Allison Jaynes

Collin Brown: "Methods for Isolation and Phase-Space Energization Analysis of Instabilities in Collisionless Shocks with Applications." Director: Greg Howes

Jayasri Joseph: Wave Particle Interplay in Planetary Magnetospheres - Case Studies from Earth and Jupiter." Director: Allison Jaynes.

Keith Vidal: Charged Particles in Magnetic Fields from Strongly Coupled Plasmas to Whistler-Mode Chorus Waves."  Director: Allison Jaynes.

NOTICE: The University of Iowa Center for Advancement is an operational name for the State University of Iowa Foundation, an independent, Iowa nonprofit corporation organized as a 501(c)(3) tax-exempt, publicly supported charitable entity working to advance the University of Iowa. Please review its full disclosure statement.