MIT News September 16, 2019
Statistics-based models to estimate the impact of unwanted noise sources surrounding qubits to create new ways to protect them generally capture simplistic Gaussian noise. A team of researchers (MIT, Dartmouth College) developed a technique to separate non-Gaussian noise from the background Gaussian noise, and then used signal-processing techniques to reconstruct highly detailed information about those noise signals. The key innovation behind the work is carefully engineering the pulses to act as specific filters that extract properties of the “bispectrum,” a two-dimension representation that gives information about distinctive time correlations of non-Gaussian noise. Those reconstructions can help researchers build more realistic noise models, which may enable more robust methods to protect qubits from specific noise types. There is now a need for such tools as qubits are being fabricated with fewer and fewer defects, which could increase the presence of non-Gaussian noise…read more. Open Access TECHNICAL ARTICLE
The tool detects new characteristics of non-Gaussian “noise” that can destroy the fragile quantum superposition state of qubits. Image courtesy of the researchers