How to Build a Better Qubit

Quantum technologies have the potential to revolutionize computing, communication, and sensing, but in order to use quantum information, we must store it for long periods of time and protect it from noise. Essentially all quantum hardware suffers from noise and loss, often arising from imperfections in the constituent materials. Understanding (and ultimately eliminating) these sources of noise is tricky business—the quantum bit (qubit) is often the most sensitive object, but merely measuring the qubit yields little information about the culprit responsible for noise. Tackling these problems requires a multidisciplinary approach that blends quantum measurement with materials science. I will describe our recent efforts to achieve major improvements in two different qubit platforms: nitrogen vacancy centers in diamond and superconducting circuits.