Seminar: How to make your favorite Josephson junction

Guest: Ahmet Mert Bozkurt, TU Delft

Title:  How to make your favorite Josephson junction

Date/Time: October 30, 2024, 13:40

Location: https://sabanciuniv.zoom.us/j/95593971575, Meeting ID: 955 9397 1575

Abstract: Josephson junctions are cornerstones of cryogenic classical and quantum superconducting technology, owing to their nonlinearity. Josephson tunnel junctions exhibit a simple current-phase relation characterized by single harmonics, whereas high-transparency Josephson junctions feature multiple harmonics depending on microscopic details of the junction, presenting a challenge for precise control. In this talk, I will illustrate that two Josephson tunnel junctions connected in series can mimic a high-transparency Josephson junction. By connecting multiple arms in parallel and adding a magnetic flux, we can systematically engineer specific current-phase relationships. As an example, I will showcase a high-efficiency superconducting diode, a two-terminal device that controls supercurrent directionally and remains robust against design imperfections, making it practical for real-world implementations. Additionally, I will present various engineered energy-phase relationships, showcasing the versatility of this technique in developing advanced quantum technologies.

Bio: A. Mert Bozkurt is a postdoctoral researcher in the Quantum Tinkerer group at TU Delft, specializing in quantum devices for quantum technologies. He is also a member of the Kitaev team in the Qubit Research Division at QuTech, a major collaborative project involving experimentalists and theorists working to realize topological qubits. Dr. Bozkurt's research spans a diverse range of topics, including quantum electronics, superconducting circuits, quantum computation, quantum 2D materials, quantum transport and thermodynamics, mesoscopic physics, and spin qubits. He earned his PhD in physics from Sabanci University, where he conducted research in Prof. Adagideli's group. Passionate about open science, Dr. Bozkurt advertises his works at the Virtual Science Forum, a volunteer-run platform that organizes and supports virtual academic events. He also submits most of his manuscripts in SciPost Physics, a two-way open-access non-profit journal with peer-witnessed refereeing.