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Quantum computers (QC) hold the promise to revolutionize various fields with their extraordinary processing power. However, several technological obstacles must be surpassed to fully unlock this potential. A primary milestone is achieving quantum advantage—the point where quantum

computers can solve certain problems more efficiently or quicker than classical computers. This necessitates an increase in the number of high-fidelity qubits, the fundamental units of quantum information. However, the scaling-up of qubits is challenging due to their immense sensitivity to

environmental noise, and a propensity for errors, making the stability of larger systems difficult. Currently, we lack the technological capability to create a large-scale, error-resistant quantum system, thereby inhibiting quantum computers from reaching their full potential and achieving

quantum advantage. Our research in the ProSQu project aims to develop a signaling module for qubits that protects them from noise, enables qubit control with low drive power, minimizes cryostat heating, and reduces noise interference. We will develop well-thermalized filters and attenuators to prevent heat generation during qubit manipulation. Leveraging our recent invention, we will implement a tunable microfilter designed to protect qubits from noise. Additionally, we will replace bulky coaxial cables with flexible cables to create a more compact setup within the cryostat. Furthermore, we plan to multiplex signals to control multiple qubits using a single line, rather than individual lines for each qubit as is currently done. Thus ProSQu offers a pragmatic solution for qubit control essential for a scaled-up quantum processor, boasting a significant

improvement in the fidelity of quantum operations. We envision a reduction in cryostat heat load by a factor of 1000, potentially enabling a quantum leap from our current 1000 qubits to millions, essential for attaining quantum advantage through fault tolerance.