qit.gate.copydot¶
- qit.gate.copydot(n_in, n_out, d=2)¶
Copy dot.
A copy dot is a tensor that copies any computational basis state, in the sense that connecting :math`ket{k}` to any of its legs breaks it up into \(n_\text{in} + n_\text{out} - 1\) unconnected copies of :math`ket{k}` and :math`bra{k}`.
\[\mathrm{COPY}^{n_\text{in} \to n_\text{out}} = \sum_{k=0}^{d-1} \ketbra{\underbrace{k \cdots k}_{n_\text{out}}}{\underbrace{k \cdots k}_{n_\text{in}}}.\]- Parameters
n_in (int) – number of input legs
n_out (int) – number of ouput legs
d (int) – leg dimension
- Returns
copy dot
- Return type
See [9]