|Title||ReQWIRE: Reasoning about Reversible Quantum Circuits|
|Publication Type||Journal Article|
|Year of Publication||2019|
|Authors||Rand, R, Paykin, J, Lee, D-H, Zdancewic, S|
|Type of Article||In Proceedings QPL 2018, arXiv:1901.09476|
Common quantum algorithms make heavy use of ancillae: scratch qubits that are initialized at some state and later returned to that state and discarded. Existing quantum circuit languages let programmers assert that a qubit has been returned to the |0> state before it is discarded, allowing for a range of optimizations. However, existing languages do not provide the tools to verify these assertions, introducing a potential source of errors. In this paper we present methods for verifying that ancillae are discarded in the desired state, and use these methods to implement a verified compiler from classical functions to quantum oracles.