Glossary

Qubitization

by Frank Zickert

Qubitization is a quantum algorithmic technique that represents a complex operator (like a Hamiltonian) as a unitary transformation acting on an extended Hilbert space, enabling efficient simulation of its dynamics. It constructs a “walk operator” whose eigenphases directly encode the eigenvalues of the target operator. This allows algorithms such as quantum phase estimation to extract those eigenvalues with optimal asymptotic scaling in precision.