Subir Sachdev


Subir Sachdev is Herchel Smith Professor of physics at Harvard University specializing in condensed matter. He was elected to the U.S. National
Academy of Sciences in 2014, received the Lars Onsager Prize from the American Physical Society and the Dirac Medal from the ICTP in 2018, and was elected Foreign Member of the Royal Society ForMemRS in 2023.
He was a co-editor of the Annual Review of Condensed Matter Physics 2017–2019, and is Editor-in-Chief of Reports on Progress in Physics since 2022.
Sachdev's research describes the consequences of quantum entanglement on the macroscopic properties of natural systems. He has described diverse varieties of entangled states of quantum matter, and of their behavior near quantum phase transitions. Many of these contributions have been linked to experiments, especially to the rich phase diagrams of the high temperature superconductors. Sachdev's research has exposed connections between the nature of quantum entanglement in certain laboratory materials, and the quantum entanglement in astrophysical black holes, and these connections have led to insights on the entropy and radiation of black holes.
WWW sachdev.physics.harvard.e...

Career

Sachdev attended school at St. Joseph's Boys' High School, Bangalore and Kendriya Vidyalaya, ASC, Bangalore. He attended college at Indian Institute of Technology, Delhi for a year. He transferred to Massachusetts Institute of Technology where he received a B.S. in Physics. He received his Ph.D. in theoretical physics from Harvard University. He held professional positions at Bell Labs and at Yale University, where he was a Professor of Physics, before returning to Harvard, where he is now the Herchel Smith Professor of Physics. He has also held visiting positions as the Cenovus Energy James Clerk Maxwell Chair in Theoretical Physics at the Perimeter Institute for Theoretical Physics, and the Dr. Homi J. Bhabha Chair Professorship at the Tata Institute of Fundamental Research. He has been a Visiting Scholar at the Flatiron Institute since 2019, and Miguel Virasoro Visiting International Chair, at the International Centre for Theoretical Physics since 2024. He has also been on the Physical Sciences jury for the Infosys Prize from 2018.

Research

Sachdev has studied the nature of quantum entanglement in two-dimensional antiferromagnets, as reviewed in his book Quantum Phases of Matter. This work introduced
  • the Z2 spin liquid, which preserves time-reversal symmetry and has the same anyon structure as the toric code.
  • deconfined quantum critical points which do not sharp particle-like excitations.
  • the fractionalized Fermi liquid, a metallic state whose Fermi surface does not enclose the Luttinger volume.
Sachdev has developed the theory of quantum criticality, elucidating its implications for experimental observations on materials at non-zero temperature. This theory led to the proposal of hydrodynamic electron flow in graphene and related two-dimensional materials. He proposed a solvable model of complex quantum entanglement in a metal which does not have any particle-like excitations in 1993: an extension of this is now called the Sachdev-Ye-Kitaev model. These works have led to a theory of quantum phase transitions in metals in the presence of impurity-induced disorder, and a universal theory of strange metals.
Sachdev's theories apply to a variety of correlated electron materials, including the copper-oxide materials exhibiting high temperature superconductivity. Features of the `pseudogap' phase of these materials are addressed by his works on the interplay between antiferromagnetism and superconductivity, using the theory of critical quantum spin liquids without quasiparticles.
A connection between the structure of quantum entanglement in the SYK model and in black holes was first proposed by Sachdev in 2010, and these connections have led to developments in the quantum theory of black holes.

Awards and honors

Publications

Books

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