... | ... | @@ -34,6 +34,9 @@ two bits of information: |
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+ a *term* of the system with higher symmetry that joins a unit cell
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of the system with lower symmetry to the system with higher symmetry.
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+ a symmetry group element that specifies which unit cell of the system
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with higher symmetry should be attached to the system of lower symmetry.
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+ a sequence of *sites* in the system with lower symmetry that
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constitute the interface.
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... | ... | @@ -98,8 +101,31 @@ a unit cell. |
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<img src="https://rawgit.com/wiki/jbweston/kwant/images/0D_2D.svg" width="50%"></img>
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We could also have a weirder configuration, where we do not cut all the hoppings.
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This means that we do not cut the higher-dimensional system into disjoint parts.
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This would look like the following:
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We could also have a weirder configuration, where we do not cut all the
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hoppings. This means that we do not cut the higher-dimensional system into
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disjoint parts. This would look like the following:
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<img src="https://rawgit.com/wiki/jbweston/kwant/images/0D_2D_weird_connection.svg" width="50%"></img>
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### Scattering region with Hole
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We may also wish to join pieces of a finite system via a region with some
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translational symmetry. Even though we could achieve a system that looks the
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same by just having a single, finite, system we can use the fact that the
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joining piece is translationally invariant to performa mode decomposition
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here. In the example below we have a ring which is cut through by a
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translationally invariant bridge.
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<img src="https://rawgit.com/wiki/jbweston/kwant/images/ring_bridge.svg" width="100%"></img>
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### Corner
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Another example which shows the generality of this approach is a corner.
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This may be used to represent a macroscopic 2D lead that we will then attach to
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some finite scattering region.
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The example below shows how to construct such a thing from a 2D translationally
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invariant part with 2 1D translationally invariant boundaries and finally a 0D
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part that connects the 2 1D boundaries.
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<img src="https://rawgit.com/wiki/jbweston/kwant/images/corner.svg" width="100%"></img> |