title: Spin-lattice relaxation times of single donors and donor clusters in silicon.
abstract: An atomistic method of calculating the spin-lattice relaxation times (T₁) is presented for donors in silicon nanostructures comprising of millions of atoms. The method takes into account the full band structure of silicon including the spin-orbit interaction. The electron-phonon Hamiltonian, and hence, the deformation potential, is directly evaluated from the strain-dependent tight-binding Hamiltonian. The technique is applied to single donors and donor clusters in silicon, and explains the variation of T₁ with the number of donors and electrons, as well as donor locations. Without any adjustable parameters, the relaxation rates in a magnetic field for both systems are found to vary as B⁵, in excellent quantitative agreement with experimental measurements. The results also show that by engineering electronic wave functions in nanostructures, T₁ times can be varied by orders of magnitude.
authors.affiliation: Network for Computational Nanotechnology, Purdue University, West Lafayette, Indiana 47907, USA.
authors.forename: Yu-Ling
authors.initials: YL
authors.lastname: Hsueh
authors.affiliation: Center for Quantum Computation and Communication Technology, School of Physics, University of New South Wales, Sydney, NSW 2052, Australia.
authors.forename: Holger
authors.initials: H
authors.lastname: Büch
authors.affiliation: Network for Computational Nanotechnology, Purdue University, West Lafayette, Indiana 47907, USA.
authors.forename: Yaohua
authors.initials: Y
authors.lastname: Tan
authors.affiliation: Network for Computational Nanotechnology, Purdue University, West Lafayette, Indiana 47907, USA.
authors.forename: Yu
authors.initials: Y
authors.lastname: Wang
authors.affiliation: Center for Quantum Computation and Communication Technology, School of Physics, University of Melbourne, VIC 3010, Australia.
authors.forename: Lloyd C L
authors.initials: LC
authors.lastname: Hollenberg
authors.affiliation: Network for Computational Nanotechnology, Purdue University, West Lafayette, Indiana 47907, USA.
authors.forename: Gerhard
authors.initials: G
authors.lastname: Klimeck
authors.affiliation: Center for Quantum Computation and Communication Technology, School of Physics, University of New South Wales, Sydney, NSW 2052, Australia.
authors.forename: Michelle Y
authors.initials: MY
authors.lastname: Simmons
authors.affiliation: Network for Computational Nanotechnology, Purdue University, West Lafayette, Indiana 47907, USA.
authors.forename: Rajib
authors.initials: R
authors.lastname: Rahman