... | ... | @@ -14,15 +14,15 @@ problems in arbitrary dimensions. Examples include: |
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+ Finite scattering region attached to 1D leads
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<img src="https://raw.githubusercontent.com/wiki/jbweston/kwant/images/0D_1D_sketch.svg" width="50%"></img>
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<img src="https://cdn.rawgit.com/wiki/jbweston/kwant/images/0D_1D_sketch.svg" width="50%"></img>
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+ 1D scattering region attached to 2D leads (+ higher dimensional
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generalizations)
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<img src="https://raw.githubusercontent.com/wiki/jbweston/kwant/images/1D_2D_sketch.svg" width="50%"></img>
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<img src="https://cdn.rawgit.com/wiki/jbweston/kwant/images/1D_2D_sketch.svg" width="50%"></img>
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+ Finite scattering region embedded in 2D bulk (+ higher dimensional
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generalizations)
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<img src="https://raw.githubusercontent.com/wiki/jbweston/kwant/images/0D_2D_sketch.svg" width="50%"></img>
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<img src="https://cdn.rawgit.com/wiki/jbweston/kwant/images/0D_2D_sketch.svg" width="50%"></img>
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## `CompositeSystem` API
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... | ... | @@ -44,22 +44,30 @@ sites in the system with lower symmetry) to be defined. |
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The symmetry group of the system with lower symmetry must be a subgroup of
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the symmetry group of the system with higher symmetry.
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The following examples should serve to illustrate the point.
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In the following illustrations, the circles correspond to a single unit cell
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of the system under consideration. Circles with dashed outline represent the
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image of the unit cell under the action of the symmetry of the system; they
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are shown for clarity. Full lines denote a set of *terms* associated with
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a symmetry group element.
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### Finite scattering region attached to 1D leads
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##### Nearest neighbor hoppings
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<img src="https://cdn.rawgit.com/wiki/jbweston/kwant/images/0D_1D.svg" width="50%"></img>
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##### Next-nearest neighbor hoppings
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<img src="https://cdn.rawgit.com/wiki/jbweston/kwant/images/0D_1D_nn.svg" width="50%"></img>
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### 1D scattering region attached to 2D leads
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<img src="https://cdn.rawgit.com/wiki/jbweston/kwant/images/1D_2D.svg" width="50%"></img>
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<img src="https://cdn.rawgit.com/wiki/jbweston/kwant/images/1D_2D_nn.svg" width="50%"></img>
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### Finite scattering region embedded in 2D bulk
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Note that we *must* choose the unit cell of the system with higher symmetry to
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be large enough so that the finite scattering region fits inside it. Otherwise
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it is impossible to describe the interface using the scheme we have outlined
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above. |
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<img src="https://cdn.rawgit.com/wiki/jbweston/kwant/images/0D_2D.svg" width="50%"></img>
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<img src="https://cdn.rawgit.com/wiki/jbweston/kwant/images/0D_2D_weird_connection.svg" width="50%"></img> |