Research

In the last decades, superconducting circuits have explosively advanced, enabling the routine exploitation of quantum effects in solid-state quantum technologies. The Josephson effect underlies this development, yet many questions persist. My PhD thesis explores fundamental and applied aspects of superconducting circuits using Josephson weak-links. Titled “Superconducting circuits with metallic and semiconducting weak-links”, it can be accessed here.

At Google, the Quantum AI team is building a useful quantum computer using superconducting circuits. Making a quantum computer function well involves fine-tuning different parts, and parametric amplifiers are key components as they allow fast single-shot readout of superconducting qubits. However, optimising their performance is not an easy task. For more on my work with the Quantum AI team, see this Google blog post.

A classical battery converts chemical energy into a persistent voltage bias capable of powering electronic circuits. Similarly, a phase battery is a quantum device that provides a continuous phase bias to the wavefunction of a superconducting circuit. In our research, we achieved the first demonstration of a phase battery in a nanowire-based Josephson junction. Read more in Nature Nanotechnology.

Shapiro steps are quantized voltage plateaus that emerge in a Josephson junction under an alternating bias, forming the foundation of the metrological voltage standard. Our research uncovered an unexpected half-integer quantization, and we delved into its origin in a Josephson junction based on a nanoflag. Read more here.