Noise Spectroscopy Without Dynamical Decoupling Pulses

Spectral characterization of noise environments that lead to the decoherence of qubits is critical to developing robust quantum technologies. While dynamical decoupling offers one of the most successful approaches to characterize noise spectra, it necessitates applying large sequences of π pulses that increase the complexity and cost of the method. In this talk, I will introduce a noise spectroscopy method that utilizes only the Fourier transform of free induction decay measurements, thus removing the need for the application any π pulses. This method faithfully recovers the correct noise spectra and outperforms previous dynamical decoupling schemes while significantly reducing its experimental overhead. I will also discuss the experimental feasibility of our proposal and demonstrate its robustness in the presence of statistical measurement noise. Our method is applicable to a wide range of quantum platforms and provides a simpler path toward a more accurate spectral characterization of quantum devices, thus offering possibilities for tailored decoherence mitigation.