Finite Length Effects and Coulomb Interaction in Ge Quantum Well-Based Josephson Junctions Probed with Microwave Spectroscopy
arXiv:2508.06180 · doi:10.1103/hb1h-8jn9
Abstract
Proximitized Ge quantum wells have emerged as a novel platform for studying Andreev bound states (ABSs), due to their expected strong spin-orbit interaction and high mobility. Here, we used microwave spectroscopy techniques to investigate ABSs in Josephson junctions (JJs) realized in proximitized Ge quantum wells. Spectroscopic signatures observed in a 350 nm junction indicated the presence of multiple ABSs, and were reproduced with a model including finite-length effects. The ABS spectra measured for a m junction were explained by a model including three ABSs in two conduction channels and finite Coulomb interaction. Our work highlights the importance of interactions in JJs and serves as a basis for understanding and manipulating ABSs in Ge-based hybrid devices.
References in corpus (23)
- Efficient and robust analysis of complex scattering data under noise in microwave resonators
- Coherent manipulation of an Andreev spin qubit
- Squeezed hole spin qubits in Ge quantum dots with ultrafast gates at low power
- Andreev spin qubits in multichannel Rashba nanowires
- Hard superconducting gap in germanium
- Signatures of interactions in the Andreev spectrum of nanowire Josephson junctions
- Circuit-QED with phase-biased Josephson weak links
- Phase-engineering the Andreev band structure of a three-terminal Josephson junction
- From adiabatic to dispersive readout of quantum circuits
- Phase-dependent microwave response of a graphene Josephson junction
- Impact of interface traps on charge noise, mobility and percolation density in Ge/SiGe heterostructures
- Planar Josephson junctions in germanium: Effect of cubic spin-orbit interaction
- Microwave spectroscopy of interacting Andreev spins
- Flip-chip-based microwave spectroscopy of Andreev bound states in a planar Josephson junction
- Microwave spectroscopy of Andreev states in InAs nanowire-based hybrid junctions using a flip-chip layout
- Enhanced orbital magnetic field effects in Ge hole nanowires
- A quantum dot in germanium proximitized by a superconductor
- Direct microwave spectroscopy of Andreev bound states in planar Ge Josephson junctions
- Microwave Sensing of Andreev Bound States in a Gate-Defined Superconducting Quantum Point Contact
- Ground state phase diagram and "parity flipping'' microwave transitions in a gate-tunable Josephson Junction
- Flip-chip-based fast inductive parity readout of a planar superconducting island
- Microwave Andreev bound state spectroscopy in a semiconductor-based Planar Josephson junction
- Approaching the ultrastrong coupling regime between an Andreev level and a microwave resonator