Quantum circuit architecture can encode task-specific spectral structure as a fixed parameter that reshapes the circuit's learning space, improving performance on frequency-based tasks without requiring more data or parameters.
This paper shows how quantum circuits can be designed with built-in biases that match specific tasks by encoding a fixed 'spectral query' alongside variable input data. The query acts like a tuning knob that changes which frequency combinations the circuit learns, without adding new information—similar to how radar systems probe signals at specific frequencies.