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Title: Efficient Quantum Circuit Decompositions via Intermediate Qudits
Many quantum algorithms make use of ancilla, additional qubits used to store temporary information during computation, to reduce the total execution time. Quantum computers will be resource-constrained for years to come so reducing ancilla requirements is crucial. In this work, we give a method to generate ancilia out of idle qubits by placing some in higher-value states, called qudits. We show how to take a circuit with many O(n) ancilla and design an ancilla-free circuit with the same asymptotic depth. Using this, we give a circuit construction for an in-place adder and a constant adder both with O(log n) depth using temporary qudits and no ancilla.
Authors:
; ;
Award ID(s):
1730449
Publication Date:
NSF-PAR ID:
10213496
Journal Name:
Proceedings of the 50th International Symposium on Multiple-Valued Logic
Page Range or eLocation-ID:
303 to 308
Sponsoring Org:
National Science Foundation
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