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We propose a minimal effective impurity model that captures the phenomenology of the Mott-Hubbard metal-insulator transition (MIT) of the half-filled Hubbard model on the Bethe lattice in infinite dimensions as observed by dynamical mean field theory (DMFT). This involves extending the standard Anderson impurity model Hamiltonian to include an explicit Kondo coupling (J), as well as a local on-site correlation (U_b) on the conduction bath site connected directly to the impurity.
Emergent Phenomena in Quantum Matter
EPQM is a condensed matter group at IISER Kolkata, led by Siddhartha Lal. We explore emergent phenomena in strongly correlated quantum matter.
EPQM in a nutshell Research Members
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An outstanding challenge involves understanding the many-particle entanglement of liquid states of quantum matter that arise in systems of interacting electrons. The Fermi liquid (FL) in (D) spatial dimensions shows a violation of the area-law in real-space entanglement entropy of a subsystem (of length (L)), (S_{EE} \sim L^{D-1}\ln L), widely believed to be a hallmark signature of the ground state of a gapless quantum critical system of interacting fermions.
Emergent Phenomena in Quantum Matter
EPQM is a condensed matter group at IISER Kolkata, led by Siddhartha Lal. We explore emergent phenomena in strongly correlated quantum matter.
EPQM in a nutshell Research Members
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We study the overscreened multi-channel Kondo (MCK) model using the recently developed unitary renormalization group (URG) technique. Our results display the importance of ground state degeneracy in explaining various important properties like the breakdown of screening and the presence of local non-Fermi liquids.
Emergent Phenomena in Quantum Matter
EPQM is a condensed matter group at IISER Kolkata, led by Siddhartha Lal. We explore emergent phenomena in strongly correlated quantum matter.
EPQM in a nutshell Research Members
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On performing a sequence of renormalisation group (RG) transformations on a system of two-dimensional non-interacting Dirac fermions placed on a torus, we demonstrate the emergence of an additional spatial dimension arising out of the scaling of multipartite entanglement. The renormalisation of entanglement under this flow exhibits a hierarchy across scales as well as number of parties.
Emergent Phenomena in Quantum Matter
EPQM is a condensed matter group at IISER Kolkata, led by Siddhartha Lal. We explore emergent phenomena in strongly correlated quantum matter.
EPQM in a nutshell Research Members
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It is well known that the topological entanglement entropy ((S_{topo})) of a topologically ordered ground state in 2 spatial dimensions can be captured efficiently by measuring the tripartite quantum information ((I^{3})) of a specific annular arrangement of three subsystems. However, the nature of the general N-partite information ((I^{N})) and quantum correlation of a topologically ordered ground state remains unknown.
Emergent Phenomena in Quantum Matter
EPQM is a condensed matter group at IISER Kolkata, led by Siddhartha Lal. We explore emergent phenomena in strongly correlated quantum matter.
EPQM in a nutshell Research Members
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We introduce a novel momentum space entanglement renormalization group (MERG) scheme for the topologically ordered (T.O.) ground state of the 2D Hubbard model on a square lattice (\cite{anirbanmotti,anirbanmott2}) using a unitary quantum circuit comprised of non-local unitary gates. At each MERG step, the unitary quantum circuit disentangles a set of electronic states, thereby transforming the tensor network representation of the many-particle state.
Emergent Phenomena in Quantum Matter
EPQM is a condensed matter group at IISER Kolkata, led by Siddhartha Lal. We explore emergent phenomena in strongly correlated quantum matter.
EPQM in a nutshell Research Members
Publication News
NOV 2023. We provide a Hamiltonian-based explanation of the DMFT-based phenomenology of the infinite dimensional Hubbard model, obtaining novel insights on the Mott MIT in the process. Learn More
MAY 2023. In a work that appeared recently at New Journal of Physics, Patra et al classify various emergent phases of matter in terms of entanglement measures. Learn More
MAY 2023. In this work, we elucidate the importance of ground-state degeneracy and frustration in determining the physics of the multichannel Kondo model. Learn More
FEB 2023. We show the emergence of an additional dimension arising out of the scaling of multipartite entanglement upon applying RG transformations on 2D noninteracting electrons placed on a torus. Learn More
Miscellaneous News
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We welcome Sukalyan Deb, our new PhD student, into the group. Learn More AUG 22, 2023
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Welcome, Aashish, to EPQM@IISER Kolkata! Learn More JUN 30, 2023
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Congratulations, Abhirup, on presenting your work at PP65@IISER Kolkata! Learn More JUN 28, 2023
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