Energy-efficient quantum computing

Abstract

Quantum computers: Energy efficient quantum control with recycled pulses The energy efficiency of a large-scale quantum computer can be improved by using fewer pulses to control more qubits. Joni Ikonen and co-workers from Aalto University (Finland) and Yale University (United States) present a theoretical scheme to manipulate qubits using a single itinerant control pulse. This is in contrast to the current mainstream prototypes where each qubit is usually controlled from room temperature through dedicated transmission lines and control pulses. The study finds that a single pulse can be recycled since its quantum state does not significantly change after interactions with the qubits. Therefore, compared to controlling qubits individually, the recycling method requires in total less energy for gate operations of equal precision. Designs based on similar redistribution of pulses may offer more efficient utilization of the control hardware in future large-scale quantum computers.