Quantum Computer Hardware: High-Frequency Excitation

To excite defined quantum states, high-frequency signals are required. The challenge lies in generating these signals with defined amplitudes and phases, delivering kilowatt-level power at frequencies in the double-digit gigahertz range. Current demonstrators typically rely on high-quality laboratory measurement technology and signal sources, which are both expensive and not tailored to the specific application. Therefore, a flexible and quantum-computer-specific high-frequency signal source is to be designed, allowing for cost-efficient and compact excitation of defined quantum states. Initially, the required output power will be generated using a commercial amplifier. The signal generation is based on a software-defined radio approach, enabling extremely fast control of magnitude and phase programmatically, depending on the real signals influenced by non-idealities of the entire quantum computer. Alongside this digital control electronics, the actual signal generation and measurement technology for the non-ideal signal properties are the main focus. Close collaboration with the research group led by PI Riedinger (UHH) is planned.

Figure: TUHH/Kölpin