James P. Eisenstein
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.
