Researchers Cut CNOT Gate Count To 12 For Qubit Excitation

A 12-CNOT decomposition of the double qubit excitation operator has been achieved, a key component in several quantum algorithms. This new circuit improves upon state-of-the-art implementations previously requiring 13 CNOTs, while also achieving the lowest CNOT depth and total circuit depth, with only two additional one-qubit gates compared to existing methods.

A new level of efficiency in quantum computation has been achieved by designing a circuit requiring fewer controlled-NOT gates, or CNOTs. These gates are fundamental to quantum processing, and reducing their number minimises potential errors and aids in scaling up quantum processors.

The team demonstrated the first decomposition of the double qubit excitation operator, using only 12 CNOTs, an improvement over previous methods needing 13. A strong advance in quantum computing has been made by designing a more efficient circuit for manipulating qubits.

Reducing the number of controlled-NOT gates, or CNOTs, which act as switches flipping a qubit’s state based on another, similar to logic gates in conventional computers, is vital for building larger, more reliable quantum processors. This new circuit also boasts the lowest ‘circuit depth’, akin to the number of steps in a recipe, and requires only two additional one-qubit gates compared to existing methods.