Read's early work concerned the properties of rare-earth "heavy-fermion" compounds, for which he developed a 1/N expansion method using gauge-theory techniques to treat the strongly interacting Kondo and heavy fermion models as constrained systems.[5][7]
Fractional quantum Hall effect
Read is best known for his work on the fractional quantum Hall effect. Together with Greg Moore, he proposed the Moore–Read state, a Pfaffian trial wavefunction for the quantum Hall plateau at filling fraction 5/2 that supports quasiparticle excitations obeying non-Abelianbraiding statistics.[8] Such excitations could in principle be used for topological quantum computation, storing quantum information non-locally and thereby achieving robustness against decoherence. With B. I. Halperin and P. A. Lee, Read developed the HLR theory, a Chern–Simons gauge theory of composite fermion Fermi liquid states at filling fraction ν = 1/2, which successfully explained a number of experimental puzzles in half-filled Landau levels.[9] Read was awarded the 2002 Oliver E. Buckley Condensed Matter Prize together with Jainendra Jain and Robert Willet "For theoretical and experimental work establishing the composite fermion model for the half-filled Landau level and other quantized Hall systems".[5]
With Edward Rezayi, Read extended the theory to construct a series of non-Abelian quantum Hall states based on parafermions in the first excited Landau level.[10]
Majorana zero modes and paired superfluids
With Dmitry Green, Read showed that p-wave (px + ipy) paired superfluids in two dimensions support Majorana zero modes bound to vortex cores, connecting the physics of paired superfluids to the non-Abelian statistics of the Moore–Read quantum Hall state.[11]
Hall viscosity
Read introduced the concept of Hall viscosity, a non-dissipative transport coefficient analogous to the Hall conductivity, and showed that it is quantized in gapped or topological phases of quantum fluids, being related to the mean orbital spin per particle.[12][13]
Other contributions
Using gauge-theory and large-N methods applied to quantum antiferromagnets, Read showed that phases without Néel order can be understood as topological phases, including spin-Peierls states and featureless spin-liquid resonating valence bond states that are essentially equivalent to the toric code.[7] In conformal field theory, Read obtained exact results on irrational CFTs arising from loop models, particularly for percolation and the spin quantum Hall transition.[7] He has also contributed to the understanding of replica symmetry breaking in short-range spin glasses.[14]
