7 citations · 23 across the 14 of their papers we have counts for
14 papers
Kramers pseudospin and the quantum number proposed for the many-electron Dirac?Coulomb Hamiltonian
Shadan Ghassemi Tabrizi
The square of a sum of single-electron time reversals has been proposed as a conserved quantity with an integer eigenvalue spectrum for the many-electron Dirac-Coulomb Hamiltonian…
Systematic extinctions in inelastic neutron scattering from molecular spin clusters
Shadan Ghassemi Tabrizi
Inelastic neutron scattering on a single crystal resolves how the intensity of a magnetic transition of a molecular spin cluster varies with the momentum-transfer vector $\mathbf{Q…
Hidden symmetry at the diabolical points of a biaxial spin
Shadan Ghassemi Tabrizi
In a rotated frame the biaxial spin Hamiltonian is a finite tight-binding chain whose hopping amplitudes are tuned by the applied fiel…
GPU-accelerated finite-temperature Lanczos method for Heisenberg spin systems with non-Abelian permutation symmetries
Shadan Ghassemi Tabrizi, Thomas D. Kühne
We extend a recent GPU implementation of the finite-temperature Lanczos method (FTLM) for Heisenberg spin Hamiltonians, which uses only total-magnetization symmetry, to the full pe…
GPU-accelerated finite-temperature Lanczos method for spin Hamiltonians
Shadan Ghassemi Tabrizi, Thomas D. Kühne
We present a GPU implementation of the finite-temperature Lanczos method (FTLM) for Heisenberg spin Hamiltonians that targets workstation hardware rather than distributed-memory cl…
SCF framework, HF stability and RPA correlation for Jordan-Wigner-transformed spin Hamiltonians on arbitrary coupling topologies
Shadan Ghassemi Tabrizi, Thomas M. Henderson, Thomas D. Kühne +1
Mapping spins to fermions via the Jordan-Wigner (JW) transformation can render mean-field (Hartree-Fock, HF) descriptions effective for strongly correlated spin systems. As establi…
Scalable implementations of mean-field and correlation methods based on Lie-algebraic similarity transformation of spin Hamiltonians in the Jordan-Wigner representation
Shadan Ghassemi Tabrizi, Thomas M. Henderson, Thomas D. Kühne +1
Recent work has highlighted that the strong correlation inherent in spin Hamiltonians can be effectively reduced by mapping spins to fermions via the Jordan-Wigner transformation (…
Simultaneous Spin and Point-Group Adaptation in Exact Diagonalization of Spin Clusters
Shadan Ghassemi Tabrizi, Thomas D. Kühne
While either spin or point-group adaptation is straightforward when considered independently, the standard technique for factoring isotropic spin Hamiltonians by the total spin S a…
Projective spin adaptation for the exact diagonalization of isotropic spin clusters
Shadan Ghassemi Tabrizi, Thomas D. Kühne
Spin Hamiltonians, like the Heisenberg model, are used to describe magnetic properties of exchange-coupled molecules and solids. For finite clusters, physical quantities such as he…
Analytical solutions of symmetric isotropic spin clusters
Shadan Ghassemi Tabrizi, Thomas D. Kühne
Spin models like the Heisenberg Hamiltonian effectively describe the interactions of open-shell transition-metal ions on a lattice and can account for various properties of magneti…
Hartree-Fock-Bogoliubov theory for number-parity--violating fermionic Hamiltonians
Thomas M. Henderson, Shadan Ghassemi Tabrizi, Guo P. Chen +1
It is usually asserted that physical Hamiltonians for fermions must contain an even number of fermion operators. This is indeed true in electronic structure theory. However, when t…
Ground states of Heisenberg spin clusters from a cluster-based projected Hartree-Fock approach
Shadan Ghassemi Tabrizi, Carlos A. Jiménez-Hoyos
Recent work on approximating ground states of Heisenberg spin clusters by projected Hartree-Fock theory (PHF) is extended to a cluster-based ansatz (cPHF). Whereas PHF variationall…
Ground States of Heisenberg Spin Clusters from Projected Hartree-Fock Theory
Shadan Ghassemi Tabrizi, Carlos A. Jiménez-Hoyos
We apply Projected Hartree-Fock theory (PHF) for approximating ground states of Heisenberg spin clusters. Spin-rotational, point-group and complex-conjugation symmetry are variatio…
Symmetry-Induced Universal Momentum-Transfer Dependencies for Inelastic Neutron Scattering on Anisotropic Spin Clusters
Shadan Ghassemi Tabrizi
Inelastic neutron scattering (INS) is a key method for studying magnetic excitations in spin systems, including molecular spin clusters. The method has significantly advanced in re…