411 citations · 900 across the 13 of their papers we have counts for
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The elementary excitations of the BCS model in the canonical ensemble
G. Sierra, J. M. Roman, J. Dukelsky
We summarize previous works on the exact ground state and the elementary excitations of the exactly solvable BCS model in the canonical ensemble. The BCS model is solved by Richard…
What are the elementary excitations of the BCS model in the canonical ensemble?
J. M. Roman, G. Sierra, J. Dukelsky
We have found the elementary excitations of the exactly solvable BCS model for a fixed number of particles. These turn out to have a peculiar dispersion relation, some of them with…
Large N limit of the exactly solvable BCS model: analytics versus numerics
J. M. Roman, G. Sierra, J. Dukelsky
We have studied the numerical solutions of Richardson equations of the BCS model in the limit of large number of energy levels at half-filling, and compare them with the analytic r…
Exact Study of the Effect of Level Statistics in Ultrasmall Superconducting Grains
G. Sierra, J. Dukelsky, G. G. Dussel +2
The reduced BCS model that is commonly used for ultrasmall superconducting grains has an exact solution worked out long ago by Richardson in the context of nuclear physics. We use…
The Crossover from the Bulk to the Few-Electron limit in Ultrasmall Metallic Grains
J. Dukelsky, G. Sierra
We study the properties of ultrasmall metallic grains with sizes in the range of 20 up to 400 electrons. Using a particle-hole version of the DMRG method we compute condensation en…
A Density Matrix Renormalization Group Study of Ultrasmall Superconducting Grains
J. Dukelsky, G. Sierra
We apply the DMRG method to the BCS pairing Hamiltonian which describes ultrasmall superconducting grains. Our version of the DMRG uses the particle (hole) states around the Fermi…