149 citations · 619 across the 40 of their papers we have counts for
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The Physics of Quantum 2.0: Challenges in understanding Quantum Matter
Siddhartha Lal, Mayank Shreshtha
Almost a century on from the culmination of the first revolution in quantum physics, we are poised for another. Even as we engage in the creation of impactful quantum technologies,…
Tomonaga-Luttinger liquid and quantum criticality in spin-1/2 antiferromagnetic Heisenberg chain C14H18CuN4O10 via Wilson ratio
Sharath Kumar Channarayappa, Sankalp Kumar, N. S. Vidhyadhiraja +9
The ground state of a one-dimensional spin-1/2 uniform antiferromagnetic Heisenberg chain (AfHc) is a Tomonaga-Luttinger liquid which is quantum-critical with respect to applied ma…
Kondo frustration via charge fluctuations: a route to Mott localisation
Abhirup Mukherjee, N. S. Vidhyadhiraja, A. Taraphder +1
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 lat…
Holographic entanglement renormalisation for fermionic quantum matter
Abhirup Mukherjee, Siddhartha Patra, Siddhartha Lal
We demonstrate the emergence of a holographic dimension in a system of 2D non-interacting Dirac fermions placed on a torus, by studying the scaling of multipartite entanglement mea…
Universal entanglement signatures of quantum liquids as a guide to fermionic criticality
Siddhartha Patra, Anirban Mukherjee, Siddhartha Lal
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 (…
Frustration shapes multi-channel Kondo physics: a star graph perspective
Siddhartha Patra, Abhirup Mukherjee, Anirban Mukherjee +3
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 s…
Unveiling the Kondo cloud: unitary RG study of the Kondo model
Anirban Mukherjee, Abhirup Mukherjee, N. S. Vidhyadhiraja +2
We analyze the single-channel Kondo model using the recently developed unitary renormalization group (URG) method, and obtain a comprehensive understanding of the Kondo screening c…
Origin of Topological Order in a Cooper Pair Insulator
Siddhartha Patra, Siddhartha Lal
We unveil the microscopic origin of the topologically ordered counterpart of the s-wave superconductor in this work. For this, we employ the recently developed unitary renormalisat…
Fermionic criticality is shaped by Fermi surface topology: a case study of the Tomonaga-Luttinger liquid
Anirban Mukherjee, Siddhartha Patra, Siddhartha Lal
We perform a unitary renormalization group (URG) study of the 1D fermionic Hubbard model. The formalism generates a family of effective Hamiltonians and many-body eigenstates arran…
Holographic unitary renormalization group for correlated electrons -- II: insights on fermionic criticality
Anirban Mukherjee, Siddhartha Lal
Capturing the interplay between electronic correlations and many-particle entanglement requires a unified framework for Hamiltonian and eigenbasis renormalization. In this work, we…
Holographic unitary renormalization group for correlated electrons -- I: a tensor network approach
Anirban Mukherjee, Siddhartha Lal
We present a unified framework for the renormalisation of the Hamiltonian and eigenbasis of a system of correlated electrons, unveiling thereby the interplay between electronic cor…
Holographic entanglement renormalisation of topological order in a quantum liquid
Anirban Mukherjee, Siddhartha Lal
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 (…
Magnetisation plateaux of the quantum pyrochlore Heisenberg antiferromagnet
Santanu Pal, Siddhartha Lal
We predict magnetisation plateaux ground states for Heisenberg antiferromagnets on pyrochlore lattices by formulating arguments based on gauge and spin-parity transformatio…
Correlated spin liquids in the quantum kagome antiferromagnet at finite field: a renormalisation group analysis
Santanu Pal, Anirban Mukherjee, Siddhartha Lal
We analyse the antiferromagnetic spin- XXZ model on the kagome lattice at finite external magnetic field with the help of a nonperturbative zero-temperature renormalization gr…
Non-perturbative approach to quantum liquid ground states on geometrically frustrated Heisenberg antiferromagnets
Santanu Pal, Anirban Mukherjee, Siddhartha Lal
We have formulated a twist operator argument for the geometrically frustrated quantum spin systems on the kagome and triangular lattices, thereby extending the application of the L…
Scaling theory for Mott-Hubbard transitions
Anirban Mukherjee, Siddhartha Lal
We present a renormalization group (RG) phase diagram for the electronic Hubbard model in two dimensions on the square lattice at, and away from, half filling. The RG proced…
Orbital and spin ordering physics of the MnO spinel
Santanu Pal, Siddhartha Lal
Motivated by recent experiments, we present a comprehensive theoretical study of the geometrically frustrated strongly correlated magnetic insulator MnO spinel oxide based…
Charge Fractionalization in a Mesoscopic Ring
Wade DeGottardi, Siddhartha Lal, Smitha Vishveshwara
We study the fractionalization of an electron tunneling into a strongly interacting electronic one-dimensional ring. As a complement to transport measurements in quantum wires conn…
Inelastic light scattering measurements of a pressure-induced quantum liquid in KCuF
S. Yuan, M. Kim, J. Seeley +3
Pressure-dependent, low temperature inelastic light (Raman) scattering measurements of KCuF show that applied pressure above 7 kbar suppresses a previously observe…
Two-step stabilization of orbital order and the dynamical frustration of spin in the model charge-transfer insulator KCuF3
James C. T. Lee, Shi Yuan, Siddhartha Lal +9
We report a combined experimental and theoretical study of KCuF3, which offers - because of this material's relatively simple lattice structure and valence configuration (d9, i.e.,…
From frustrated insulators to correlated anisotropic metals: charge ordering and quantum criticality in coupled chain systems
Siddhartha Lal, Mukul S. Laad
A recent study revealed the dynamics of the charge sector of a one-dimensional quarter-filled electronic system with extended Hubbard interactions to be that of an effective pseudo…
Ordering from frustration in a strongly correlated one-dimensional system
Siddhartha Lal, Mukul S. Laad
We study a one-dimensional extended Hubbard model with longer-range Coulomb interactions at quarter-filling in the strong coupling limit. We find two different charge-ordered (CO)…
Charge ordering in quasi-one-dimensional systems with frustrating interactions
Siddhartha Lal, Mukul S. Laad
Motivated by the co-existing charge and spin order found in strongly correlated ladder systems, we study an effective pseudospin model on a coupled two-leg ladder. A bosonisation a…
On charge and spin ordering in a one-dimensional model with frustrating interactions
M. S. Laad, S. Lal
We study a one-dimensional extended Hubbard model with longer-range Coulomb interactions at quarter-filling in the strong coupling limit. We find two different charge-ordered groun…