Arbitrary noise generator based on solid-state spin systems

A controlled noise environment provides a unique platform for the investigation of various quantum technologies. Here, we demonstrate a technique to engineer arbitrary unitary baths in quantum systems with solid-state spin systems. A wide variety of classical noise models, including the generation of dephasing noise and amplitude-damping noise was realized through precise modulation of microwave signals. By measuring the power spectral density of the noise with the aid of single nitrogen-vacancy (N-V) color centers in diamond, we confirm that the generated noise closely matches the theoretical expectations. This technique serves as a powerful toolkit for validating quantum control protocols, simulating decoherence processes in other quantum systems, and generating baths essential for studying quantum thermodynamics.