Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Spin-lattice relaxation times of single donors and donor clusters in
  silicon   An atomistic method of calculating the spin-lattice relaxation times ($T_1$)
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 $T_1$ 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 $B^5$ in excellent quantitative agreement with
experimental measurements. The results also show that by engineering electronic
wavefunctions in nanostructures, $T_1$ times can be varied by orders of
magnitude.

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The categories of this paper are: acc-phys
3
The categories of this paper are: physics
13
The categories of this paper are: quant-ph
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The categories of this paper are: solv-int
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The categories of this paper are: q-fin
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The categories of this paper are: dg-ga
22
The categories of this paper are: chao-dyn
10
The categories of this paper are: q-bio
5
The categories of this paper are: gr-qc
35
The categories of this paper are: mtrl-th
26
The categories of this paper are: bayes-an
33
The categories of this paper are: plasm-ph
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The categories of this paper are: q-alg
7
The categories of this paper are: hep-th
27
The categories of this paper are: comp-gas
11
The categories of this paper are: hep-lat