James P. Eisenstein

Wolf Prize Laureate in Physics 2025

James P. Eisenstein

Affiliation at the time of the award:

Caltech, USA

Award citation:

“For advancing our understanding of the surprising properties of two-dimensional electron systems in strong magnetic fields”.

Prize share:

James P. Eisenstein

Jainendra K. Jain

Mordehai Heiblum

James P. Eisenstein (1952, USA) earned his AB degree from Oberlin College in 1974 and completed a Ph.D. in physics at the University of California, Berkeley, in 1980. After serving as an assistant professor at Williams College, he joined Bell Laboratories in 1983 as a member of the technical staff. In 1996, he accepted a faculty position at the California Institute of Technology (Caltech) and became the Frank J. Roshek Professor of Physics and Applied Physics in 2005. He retired as professor emeritus in 2018 and concluded his experimental research in 2021. Eisenstein has contributed to several National Research Council committees, including the Solid State Sciences Committee and the Board on Physics and Astronomy. He also served as associate editor for the Annual Review of Condensed Matter Physics from 2014 to 2017.

The three awardees have profoundly transformed our understanding of the fractional quantum Hall effect, (a Nobel prize-winning phenomenon) in which a thin layer of electrons in a magnetic field behaves as if the electrical current is carried by particles charged with a fraction of the electron charge.
A powerful and intuitively appealing way to understand these particles was developed by Dr. Jain, who introduced the concept of a composite fermion: a particle formed by binding an electron to a magnetic flux tube. The idea that large numbers of strongly interacting electrons behave as weakly interacting composite particles explains the intricate sequence of fractional quantum Hall states observed in the laboratory, now known as the Jain states. The composite fermion theory has provided quantitatively precise agreement with numerical studies, and it has predicted and explained experiments that find behavior reminiscent of a superconductor at special values (filling fraction 5/2) of the electron density.
Dr. Heiblum pioneered the exploration of these exotic particles in the laboratory. By developing ultra-high-purity materials and electron interferometry techniques, Heiblum’s group could provide concrete evidence for the fractional charge and verify fundamental predictions, including the anomalous statistics (intermediate between that of fermions and bosons). A milestone experiment was the observation of half-integer quantized thermal conductance at filling fraction 5/2, confirming the prediction that the corresponding composite fermions are Majorana fermions, and with potential implications for quantum computation.
Dr. Eisenstein co-discovered the fractional quantum Hall state at filling factor 5/2 and went on to explore exotic phases of two-dimensional electron systems. This includes an anisotropic state where the resistance probed along one direction is much larger than the resistance along the perpendicular direction, reminiscent of a liquid crystal. Eisenstein’s development of methods to separately contact individual electron layers enabled the study of the correlated motion of electron-hole pairs in the two layers, with the breakthrough observation of their Bose-Einstein condensation.
The award of the 2025 Wolf prize to these three physicists honors their extraordinary contributions to the exploration of quantum matter, with far-reaching impact on emerging quantum technologies.

Mordehai (Moty) Heiblum

Wolf Prize Laureate in Physics 2025

Mordehai (Moty) Heiblum

Affiliation at the time of the award:

The Weizmann Institute of Science, Israel

Award citation:

“For advancing our understanding of the surprising properties of two-dimensional electron systems in strong magnetic fields”.

Prize share:

Mordehai Heiblum

Jainendra K. Jain

James P. Eisenstein

Mordehai (Moty) Heiblum (1947, Israel) is a physicist and electrical engineer, he graduated from the Technion (B.Sc., 1973) and Carnegie Mellon University (M.Sc., 1974) before earning his Ph.D. in 1978 at UC Berkeley. He began his career at the IBM Thomas J. Watson Research Center, where he worked for 12 years. In 1990, Heiblum returned to Israel to establish the Joseph H. and Belle R. Braun Center for Submicron Research at the Weizmann Institute, where he has served as director since its inception. He also founded and directed the Department of Condensed Matter Physics and holds the Alex and Ida Sussman Professorial Chair of Submicron Studies.

The three awardees have profoundly transformed our understanding of the fractional quantum Hall effect, (a Nobel prize-winning phenomenon) in which a thin layer of electrons in a magnetic field behaves as if the electrical current is carried by particles charged with a fraction of the electron charge.
A powerful and intuitively appealing way to understand these particles was developed by Dr. Jain, who introduced the concept of a composite fermion: a particle formed by binding an electron to a magnetic flux tube. The idea that large numbers of strongly interacting electrons behave as weakly interacting composite particles explains the intricate sequence of fractional quantum Hall states observed in the laboratory, now known as the Jain states. The composite fermion theory has provided quantitatively precise agreement with numerical studies, and it has predicted and explained experiments that find behavior reminiscent of a superconductor at special values (filling fraction 5/2) of the electron density.
Dr. Heiblum pioneered the exploration of these exotic particles in the laboratory. By developing ultra-high-purity materials and electron interferometry techniques, Heiblum’s group could provide concrete evidence for the fractional charge and verify fundamental predictions, including the anomalous statistics (intermediate between that of fermions and bosons). A milestone experiment was the observation of half-integer quantized thermal conductance at filling fraction 5/2, confirming the prediction that the corresponding composite fermions are Majorana fermions, and with potential implications for quantum computation.
Dr. Eisenstein co-discovered the fractional quantum Hall state at filling factor 5/2 and went on to explore exotic phases of two-dimensional electron systems. This includes an anisotropic state where the resistance probed along one direction is much larger than the resistance along the perpendicular direction, reminiscent of a liquid crystal. Eisenstein’s development of methods to separately contact individual electron layers enabled the study of the correlated motion of electron-hole pairs in the two layers, with the breakthrough observation of their Bose-Einstein condensation.
The award of the 2025 Wolf prize to these three physicists honors their extraordinary contributions to the exploration of quantum matter, with far-reaching impact on emerging quantum technologies.

Jainendra K. Jain

Wolf Prize Laureate in Physics 2025

Jainendra K. Jain

 

Affiliation at the time of the award:

The Pennsylvania State University, USA

 

Award citation:

“For advancing our understanding of the surprising properties of two-dimensional electron systems in strong magnetic fields”.

 

Prize share:

Jainendra K. Jain

Mordehai Heiblum

James P. Eisenstein

 

Jainendra K. Jain (1960, India) completed his bachelor’s degree at Maharaja College, Jaipur, followed by a master’s degree in physics from the Indian Institute of Technology (IIT) Kanpur. Jain earned his Ph.D. at Stony Brook University, where he worked under the guidance of Profs. Philip B. Allen and Steven Kivelson. After postdoctoral positions at the University of Maryland (1988) and Yale University (1989), Jain returned to Stony Brook University as a faculty member in 1989. In 1998, he joined Pennsylvania State University, where he continues his work. He has authored the monograph Composite Fermions (Cambridge University Press, 2007) and co-edited Fractional Quantum Hall Effects: New Developments (World Scientific, 2020) with Bertrand Halperin.

The three awardees have profoundly transformed our understanding of the fractional quantum Hall effect, (a Nobel prize-winning phenomenon) in which a thin layer of electrons in a magnetic field behaves as if the electrical current is carried by particles charged with a fraction of the electron charge.
A powerful and intuitively appealing way to understand these particles was developed by Dr. Jain, who introduced the concept of a composite fermion: a particle formed by binding an electron to a magnetic flux tube. The idea that large numbers of strongly interacting electrons behave as weakly interacting composite particles explains the intricate sequence of fractional quantum Hall states observed in the laboratory, now known as the Jain states. The composite fermion theory has provided quantitatively precise agreement with numerical studies, and it has predicted and explained experiments that find behavior reminiscent of a superconductor at special values (filling fraction 5/2) of the electron density.
Dr. Heiblum pioneered the exploration of these exotic particles in the laboratory. By developing ultra-high-purity materials and electron interferometry techniques, Heiblum’s group could provide concrete evidence for the fractional charge and verify fundamental predictions, including the anomalous statistics (intermediate between that of fermions and bosons). A milestone experiment was the observation of half-integer quantized thermal conductance at filling fraction 5/2, confirming the prediction that the corresponding composite fermions are Majorana fermions, and with potential implications for quantum computation.
Dr. Eisenstein co-discovered the fractional quantum Hall state at filling factor 5/2 and went on to explore exotic phases of two-dimensional electron systems. This includes an anisotropic state where the resistance probed along one direction is much larger than the resistance along the perpendicular direction, reminiscent of a liquid crystal. Eisenstein’s development of methods to separately contact individual electron layers enabled the study of the correlated motion of electron-hole pairs in the two layers, with the breakthrough observation of their Bose-Einstein condensation.
The award of the 2025 Wolf prize to these three physicists honors their extraordinary contributions to the exploration of quantum matter, with far-reaching impact on emerging quantum technologies.

Martin Rees

Wolf Prize Laureate in Physics 2024

Martin Rees

 

Affiliation at the time of the award:

Cambridge University, England

 

Award citation:

“for fundamental contributions to high-energy astrophysics, galaxies and structure formation, and cosmology”.

 

Prize share:

None

 

Lord Martin Rees (born in England in 1942) is one of the most distinguished theoretical physicists of our time, with seminal contributions in a large number of areas, from cosmology and the formation of the first stars and galaxies to high-energy astrophysics, to the formation and evolution of massive black holes in the centers of galaxies, tidal disruption of stars in the vicinity of such black holes, and more. These contributions shaped our deepest understanding of the Universe.

From a young age, with a strong background in mathematics, Rees discovered his attraction to astrophysics, which was, at that time, one of the fastest-growing areas of science, full of unexplained phenomena waiting to be explored. His first position as a professor at Sussex University, in 1973, soon brought him to the Institute of Astronomy in Cambridge, where he became the director of the institute, the Plumian Professor of Astronomy and Experimental Philosophy, and the Master of Trinity College. In later years, Rees became a Fellow, then the Royal Society President, and a House of Lords member in 2005. Since 1995, he has held the honorary title “The UK’s Astronomer Royal”.
Marin Rees has pioneered many ideas that are shaping our understanding of the Universe. In cosmology, he was the first to propose polarization measurements as a tool to probe the origin of fluctuations in the cosmic microwave background. This is now accepted as a key diagnostic tool of the very early universe. He was also an initiator of the field of 21cm cosmology, now becoming a very important tool for understanding the conditions in the universe prior to the birth of the first stars and galaxies. Another area where he made fundamental contributions is high-energy astrophysics. This includes the explanation of the physical processes driving extremely powerful Gamma-ray bursts from colliding neutron stars and a certain type of supernova, as well as the understanding of powerful radio jets from various types of galaxies. Later observations have confirmed Rees’s early theoretical works on the properties of such objects. Massive black holes in the centers of galaxies have been another area where Rees made numerous fundamental contributions, from suggesting various ways to explain the formation of individual black holes to ideas of how they produce their extremely high luminosity that can exceed the luminosity of entire galaxies and how the black hole population in the universe evolves in parallel to the cosmic evolution of galaxies. Such theoretical ideas are now being studied and confirmed by the most advanced ground-based and space borne telescopes. Other theoretical papers that have become timely because of recent observations are binary black hole mergers and the tidal disruption of stars by massive black holes, which have been discovered in dozens of galaxies.
Marin Rees is well known for his unusual ability to convey complex scientific concepts to the public. Over the years, he has delivered hundreds of public lectures and television interviews. He has written numerous general articles and popular science books on cosmology, life in the universe, black holes, and other topics of 21st-century science. The title of his recent book, from 2022, is “If Science is to Save Us.” In recent years, he has been spending much of his time in efforts to safeguard the global environment. He co-founded the “Centre for the Study of Existential Risk at the University of Cambridge,” an interdisciplinary research center that studies existential risks and fosters a global community to safeguard humanity.
Martin Rees is awarded the Wolf Prize for shaping our deepest understanding of the Universe. His outstanding contributions range from high-energy astrophysics, including mechanisms for gamma-ray bursts, powerful radio jets, and black hole formation in galactic nuclei, to cosmic structure formation and the physics of the earliest stars and galaxies at the end of the “dark age.” He was the first to propose polarization measurements as a tool to probe the origin of fluctuations and anisotropy in the cosmic microwave background (CMB), and an initiator of the field of 21cm cosmology.

Ferenc Krausz

Wolf Prize Laureate in Physics 2022

Ferenc Krausz

 

Affiliation at the time of the award:

Max Planck Institute of Quantum Optics, Germany

 

Award citation:

“for pioneering contributions to ultrafast laser science and attosecond physics”

 

Prize share:

Ferenc Krausz

Paul Corkum

Anne L’Huillier

 

“for pioneering and novel work in the fields of ultrafast laser science and attosecond physics and for demonstrating time-resolved imaging of electron motion in atoms, molecules, and solids. Each of them made crucial contributions, both to the technical development of attosecond physics and to its application to fundamental physics studies”.

 

Krausz, an Hungarian-Austrian physicist whose research team was the first to generate and measure attosecond light pulses and used them to capture electron motion inside atoms.

Krausz was awarded his MSc in Electrical Engineering at the Budapest University of Technology in 1985. His Ph.D. in Quantum Electronics is from the Vienna University of Technology, in 1991, and his “Habilitation” from the same university in 1993. He joined the Department of Electrical Engineering as Associate Professor in 1998 and became a full Professor in 1999. In 2003 he was appointed a Director in the Max Planck Institute of Quantum Optics in Garching, Germany. Since 2004, he is a Professor of Physics and Chair of Experimental Physics at the Ludwig Maximilian University of Munich. Krausz is fascinated by expeditions into ever smaller dimensions of space and time. As far back as the early 1990s, when he was working on his doctorate at the Vienna University of Technology, he was impressed by the idea to do so using extremely short pulses of light that new lasers were making possible at the time. The first attosecond pulses were generated and measured by Krausz’s group in the early 2000s. This allowed Krausz to make real-time observations of electron movements on atomic scales for the first time. Today, we are using such pulses to gain a better understanding of microscopic processes involving electrons, atoms, and molecules, and to find how they affect the macroscopic worlds.

Krausz’s recent work at the Max Planck Institute of Quantum Optics includes several exciting new applications. With his group, he attempts to use femtosecond and attosecond technology to analyze blood samples and to detect minute changes in their composition. The group investigates whether these changes are specific enough to allow diseases to be diagnosed, unambiguously, in their initial stages.

Krausz showed that the harmonic pulses have durations in the attosecond range. He also contributed to the generation of few-cycle laser pulses and the study of the time dependence of numerous atomic and molecular physics processes. He realized the feasibility of experiments with time resolution in the attosecond range. This has allowed the study of photoionization in the time-domain and evidenced Wigner-like time delays in the photoemission of electrons from atoms or molecules.

 

Paul Corkum

Wolf Prize Laureate in Physics 2022

Paul Corkum

 

Affiliation at the time of the award:

University of Ottawa, Canada

 

Award citation:

“for pioneering contributions to ultrafast laser science and attosecond physics”

 

Prize share:

Paul Corkum

Ferenc Krausz

Anne L’Huillier

 

“for pioneering and novel work in the fields of ultrafast laser science and attosecond physics and for demonstrating time-resolved imaging of electron motion in atoms, molecules, and solids. Each of them made crucial contributions, both to the technical development of attosecond physics and to its application to fundamental physics studies.”

 

Corkum, a Canadian physicist, a leader, and a pioneer in the field of ultrafast laser spectroscopy. For three decades he has been a major source of insight regarding the great potential of this field. He is known primarily for his remarkable contributions to the field of high harmonic generation and for proposing intuitive models which helped to explain the complex phenomena associated with attosecond spectroscopy.

Corkum has stated that he owes his career to his high-school physics teacher, Anthony Kennett, who pushed him to prove everything. According to Corkum, in physics, that is what you want to do. Corkum grew up in Saint John, New Brunswick, a small port city on Canada’s east coast. The son of a fisherman and tugboat captain, he spent much of
his time around boats, sailing with his father, and working on various types of engines. Corkum started his career as a theoretical physicist. He graduated from Lehigh University, PA, U.S.A., with a PhD in theoretical physics in 1973. Later, during a postdoctoral interview at the National Research Council of Canada (NRC), when asked “Why do you think you can work in experimental physics?” he replied, with confidence gained by his childhood experience that “it’s no problem, I can take the engine of a car completely apart, repair it and put it back together so it will work”. They hired him! Today, Corkum directs the Joint NRC/University of Ottawa Attosecond Science Laboratory and holds a Canada Research Chair at the University of Ottawa. He is a fellow of the Royal Societies of London and of Canada and a foreign member of the US National Academy of Science, the Austrian Academy of Science, and the Russian Academy of Sciences.

Corkum established the understanding of high harmonic generation through his semiclassical re-collision model that underlies the formation of attosecond pulses. Under the influence of a strong laser field, an electron can tunnel ionize from an atomic or a molecular potential, accelerated, and then recombine, emitting high-order harmonics. The emitted harmonic spectrum is sensitive to the evolution in time of the atomic or molecular structure. The so-called high harmonic spectroscopy allowed him
to demonstrate the feasibility to image a molecular orbital via a tomographic reconstruction procedure.

 

Anne L’Huillier

Wolf Prize Laureate in Physics 2022

Anne L’Huillier

 

Affiliation at the time of the award:

Lund University, Sweden

 

Award citation:

“for pioneering contributions to ultrafast laser science and attosecond physics”.

 

Prize share:

Anne L’Huillier

Paul Corkum

Ferenc Krausz

 

“for pioneering and novel work in the fields of ultrafast laser science and attosecond physics and for demonstrating time-resolved imaging of electron motion in atoms, molecules, and solids. Each of them made crucial contributions, both to the technical development of attosecond physics and to its application to fundamental physics studies”.

 

Anne L’Huillier Is a French/Swedish physicist and professor of atomic physics at Lund University, working on the interaction between short and intense laser pulses and atoms. As a child, she was inspired by Apollo 11, the first manned mission to land on the Moon, in 1969. She was also influenced by her grandfather, who was a professor of electrical engineering working on radio communication. The result was a great enthusiasm for science and technology, which later made her a leader in experimental attosecond physics.

L’Huillier was awarded a double master’s degree in theoretical physics and mathematics and later switched to experimental physics to complete a Ph.D. in 1986, at Université Paris VI. She was then permanently employed as researcher at the Commissariat de l’Energie Atomique (CEA). In 1987, she participated in an experiment where high-order harmonics were observed for the first time using a picosecond Nd:YAG laser system. She was fascinated by the experiment and decided to devote her  time to work in this area of research. In 1995, she moved to Lund University in Sweden where she became a full professor in 1997. In 2004 she was elected a member of the Royal Swedish Academy of Sciences.

Anne L’Huillier was among the firsts to experimentally demonstrate high harmonic generation, which is the process by which attosecond pulses form, and contributed significantly to the development of a proper theoretical description of the process. She also performed a number of seminal experiments to improve the understanding of the underlying process and was a key player in the formation of the new attosecond science research field.

 

Giorgio Parisi

Wolf Prize Laureate in Physics 2021

Giorgio Parisi

 

Affiliation at the time of the award:

University of Rome ‘‘La Sapienza’’, Italy

 

Award citation:

“for ground-breaking discoveries in disordered systems, particle physics and statistical physics”.

 

Prize share:

None

 

Giorgio Parisi, Professor of theoretical physics at the University of Rome, ‘‘La Sapienza’’, whose research has focused on quantum field theory, statistical mechanics, and complex systems.

His father and grandfather were both construction workers, and the young Parisi was encouraged to become an engineer. Instead, Parisi was drawn to the complicated abstractions he read in books of popular science, science fiction and mathematics and wanted to do something that involved research. Parisi was torn between majoring in physics and mathematics. He attracted by the adventurous nature of research and sees physics as the terrain on which to play his intellectual challenge at the highest level. Parisi graduated in physics in 1970 in the shortest possible time, under the direction of Nicola Cabibbo. Parisi’s achievements span many areas of modern physics and even the field of biological models. He is author of many books, articles and ideas that have opened up new areas of research.

The Wolf Prize in Physics is awarded to Giorgio Parisi for being one of the most creative and influential theoretical physicists in recent decades. His work has a large impact on diverse branches of physical sciences, spanning the areas of particle physics, critical phenomena, disordered systems as well as optimization theory and mathematical physics. In 1977 together with Altarelli, Parisi discovered the evolution equations allowing to accurately formulating how quarks and gluons are distributed inside the proton and nuclei (they were discovered independently by Yu. L. Dokshitzer). Parisi’s work was indispensable in analyzing the fundamental structure of matter at the smallest possible distance scale done through high-energy scattering of elementary particles. His results have served in preparing and analyzing the experiments performed at the Large-Hardon-Collider (LHC), for dark matter searches, and are used today in the planning experiments for the Future Circular Collider.

In another series of seminal works from 1979-84, Parisi introduced the concept of replica symmetry breaking and applied it to models of “spin-glasses” (the Sherrington-Kirkpatrick model), where no simple order parameter exists. His remarkable intuition led him to the discovery of the non-ergodic nature of the frustrated spin-glass phase, where many pure states unrelated by symmetry coexist, with a highly non-trivial ultra-metric structure. Parisi’s suggestion of a new organization of matter has led to a paradigm shift in statistical physics, and many applications followed in other disordered systems such as structural glasses, neural networks, and combinatorial optimization theory.

His highly innovative work (with Sourlas) in studying classical phase transitions has led to the possibility to identify the actual realization of a symmetry called supersymmetry in condensed matter systems.

 

Allan H. MacDonald

Wolf Prize Laureate in Physics 2020

Allan H. MacDonald

 

Affiliation at the time of the award:

The University of Texas at Austin, USA

 

Award citation:

“For pioneering theoretical and experimental work on twisted bilayer graphene.”

 

Prize Share:

Allan H. MacDonald 

Pablo Jarillo-Herrero

Rafi Bistritzer

 

Since the 2004 groundbreaking experiments regarding the two-dimensional material -graphene, several research groups were soon studying the properties of twisted bilayer graphene. Graphene is a significant foundation for an entirely new generation of technologies. The hope is that graphene-based applications will benefit the environment and reduce costs. Electronic and computer industry requires materials whose conductance can be controlled.

The work of Jarillo-Herrero, MacDonald and Bistrizer has shown that the conductance properties of graphene interfaces can be controlled via the spatial misfit angle between the layers and then at certain angles the electrons exhibit surprising physical behavior. This physical discovery has the potential of leading to an energy revolution.

In 2011, a group led by Allan Macdonald, a theoretical physicist from the University of Texas, researched an intriguing behavior of twisted bilayer graphene, where the atomic lattices of two stacked graphene layers are laterally rotated with respect to each other by a small misfit angle. According to the calculations of MacDonald and Bistrizer (who did his post-doctoral thesis under the supervision of MacDonald at that time), the tunneling velocity of electrons between the layers depends on the misfit angle and completely vanishes at the “magic angle” of 1.1 degrees. It was hoped that this discovery would lead to the creation of a new type of super-conductor, namely a material that allows electrical current to pass with no impedance and with no energy loss.

The original paper by MacDonald and Bistrizer, which describes their discovery, was not received with enthusiasm by the scientific community and was even forgotten for several years.

At the same time, Jarillo-Herrero was working on twisted bilayer graphene in his lab at MIT. He became convinced that the ideas expressed by Macdonald and Bistrizer had substance.

His research team  therefore invested considerable efforts in creating and measuring twisted bilayer graphene of various twist angles. The experiments proved successful in 2017 when it was found that positioning the layers at an angle of 1.1 degrees relative to one another (“the magic angle”) resulted in unusual electrical properties, precisely as MacDonald and Bistrizer have suggested. In this position, at sufficiently low temperatures, the electrons move from one layer to the other, creating a lattice with unusual qualities. The paper that described the phenomenon, which was published in Nature in 2018, revolutionized physics and triggered a flood of additional papers.

The discovery opens the door to building a super-conductor from bilayer graphene, in which electron movement is completely controlled by external electrical current. This electrical behavior resembles the behavior of copper-based superconductors called Cuprates. Cuprates demonstrate electrical conductivity with no resistance in relatively high temperatures compared with other super-conductors. For this reason, Cuprates now form a source of hope for realizing the dream of electrical conductivity with no energy loss at temperatures close to room temperature. If this mission is achieved, it would lead to a far-reaching energy revolution. However, one obstacle that prevents this revolution is that we do not yet have a theory that explains the behavior of superconductors at high temperatures. In the absence of a solid theoretical foundation, it is difficult to develop new, better materials. This is one of the reasons for the excitement around the discovery of bilayer graphene and the magic angle, which allows us to understand better what happens on the microscopic level when transitioning from a conductor to a superconductor state.

Allan H. MacDonald (1951, Canada) received the B.Sc. degree from St. Francis Xavier University, Antigonish, Nova Scotia, Canada in 1973 and the M.Sc. and Ph.D. degrees in physics from the University of Toronto in 1974 and 1978, respectively. He was a member of the research staff of the National Research Council of Canada from 1978 to 1987 and has taught at Indiana University (1987-2000) and the University of Texas at Austin (2000-present) where he now holds the Sid W. Richardson Chair in Physics. He has contributed to research on the quantum Hall effect, electronic band structure theory, magnetism, and superconductivity among a variety of other topics. Prof. MacDonald is a fellow of the American Physical Society, a member of the American Academy of Arts and Sciences and the US National Academy of Sciences, and a recipient of the Herzberg Medal, the Ernst Mach Honorary Medal, and the Buckley Prize.

Pablo Jarillo-Herrero

Wolf Prize Laureate in Physics 2020

Pablo Jarillo-Herrero

 

Affiliation at the time of the award:

Massachusetts Institute of Technology, USA

 

Award citation:

“For pioneering theoretical and experimental work on twisted bilayer graphene.”

 

Prize Share:

Pablo Jarillo-Herrero

Allan H. MacDonald 

Rafi Bistritzer

 

Since the 2004 groundbreaking experiments regarding the two-dimensional material-graphene, several research groups were soon studying the properties of twisted bilayer graphene. Graphene is a significant foundation for an entirely new generation of technologies. The hope is that graphene-based applications will benefit the environment and reduce costs. Electronic and computer industry requires materials whose conductance can be controlled.

The work of Jarillo-Herrero, MacDonald and Bistrizer has shown that the conductance properties of graphene interfaces can be controlled via the spatial misfit angle between the layers and then at certain angles the electrons exhibit surprising physical behavior. This physical discovery has the potential of leading to an energy revolution.

In 2011, a group led by Allan Macdonald, a theoretical physicist from the University of Texas, researched an intriguing behavior of twisted bilayer graphene, where the atomic lattices of two stacked graphene layers are laterally rotated with respect to each other by a small misfit angle. According to the calculations of MacDonald and Bistrizer (who did his post-doctoral thesis under the supervision of MacDonald at that time), the tunneling velocity of electrons between the layers depends on the misfit angle and completely vanishes at the “magic angle” of 1.1 degrees. It was hoped that this discovery would lead to the creation of a new type of super-conductor, namely a material that allows electrical current to pass with no impedance and with no energy loss.

The original paper by MacDonald and Bistrizer, which describes their discovery, was not received with enthusiasm by the scientific community and was even forgotten for several years.

At the same time, Jarillo-Herrero was working on twisted bilayer graphene in his lab at MIT. He became convinced that the ideas expressed by Macdonald and Bistrizer had substance.

His research team therefore invested considerable efforts in creating and measuring twisted bilayer graphene of various twist angles. The experiments proved successful in 2017 when it was found that positioning the layers at an angle of 1.1 degrees relative to one another (“the magic angle”) resulted in unusual electrical properties, precisely as MacDonald and Bistrizer have suggested. In this position, at sufficiently low temperatures, the electrons move from one layer to the other, creating a lattice with unusual qualities. The paper that described the phenomenon, which was published in Nature in 2018, revolutionized physics and triggered a flood of additional papers.

The discovery opens the door to building a super-conductor from bilayer graphene, in which electron movement is completely controlled by external electrical current.

This electrical behavior resembles the behavior of copper-based superconductors called Cuprates. Cuprates demonstrate electrical conductivity with no resistance in relatively high temperatures compared with other super-conductors. For this reason, Cuprates now form a source of hope for realizing the dream of electrical conductivity with no energy loss at temperatures close to room temperature. If this mission is achieved, it would lead to a far-reaching energy revolution. However, one obstacle that prevents this revolution is that we do not yet have a theory that explains the behavior of superconductors at high temperatures. In the absence of a solid theoretical foundation, it is difficult to develop new, better materials. This is one of the reasons for the excitement around the discovery of bilayer graphene and the magic angle, which allows us to understand better what happens on the microscopic level when transitioning from a conductor to a superconductor state.

Pablo Jarillo-Herrero (1976, Valencia) is an experimental condensed matter physicist who works on quantum electronic transport and optoelectronics in novel two-dimensional materials. His lab investigates their superconducting, magnetic, and topological properties. Jarillo-Herrero joined MIT in 2008 and was promoted to full professor in 2018. He received his ”licenciatura” in physics from the University of Valencia in Spain, in 1999; a master of science degree from the University of California at San Diego in 2001; and his PhD from the Delft University of Technology in the Netherlands, in 2005.