6533b86cfe1ef96bd12c81da
RESEARCH PRODUCT
Exact Coulomb cutoff technique for supercell calculations in two dimensions
Esa RäsänenCarlo Andrea RozziAndrea Castrosubject
Coulomb operatorPhysicsFOS: Physical sciencessupercell calculationsCondensed Matter PhysicsElectronic Optical and Magnetic MaterialsCondensed Matter - Other Condensed MatterReciprocal latticeDimension (vector space)Quantum dotQuantum mechanicsSupercell (crystal)CoulombCutoffQuantum informationOther Condensed Matter (cond-mat.other)description
We present a reciprocal space technique for the calculation of the Coulomb integral in two dimensions in systems with reduced periodicity, i.e., finite systems, or systems that are periodic only in one dimension. The technique consists in cutting off the long-range part of the interaction by modifying the expression for the Coulomb operator in reciprocal space. The physical result amounts in an effective screening of the spurious interactions originated by the presence of ghost periodic replicas of the system. This work extends a previous report [C. A. Rozzi et al., Phys. Rev. B 73, 205119 (2006)], where three-dimensional systems were considered. We show that the use of the cutoffs dramatically enhances the accuracy of the calculations for a given supercell size, and it allows to describe two-dimensional systems of reduced periodicity with substantially less computational effort. In particular, we consider semiconductor quantum-dot arrays having potential applications in quantum information technology.
| year | journal | country | edition | language |
|---|---|---|---|---|
| 2009-01-01 |