Critical Josephson current in the dynamical Coulomb blockade regime

Abstract

Superconductivity is commonly described as a macroscopic quantum phenomenon. However, it arises from microscopic mechanisms occurring at the nanometer scale as illustrated, for example, by the non-trivial pairing in unconventional superconductors. More recently, also local interactions with superconductors in the context of Majorana fermions became of interest. A very direct way to study the atomic scale properties of superconductors is given by the combination of the Josephson effect with scanning tunneling microscopy (STM), also referred to as JSTM. Here, the critical Josephson current serves as a direct local probe of the superconducting ground state and may reveal valuable information that is often inaccessible when studying quasi-particle excitation spectra. We show that we can extract local values of the critical Josephson current from JSTM measurements in the dynamical Coulomb blockade regime. Furthermore, we experimentally determine the regime of sequential Cooper pair tunneling, which is in accordance to theoretical predictions. Our study presents new insights on the tunneling mechanisms in Josephson junctions and lays the basis for the implementation of JSTM as a versatile probe for superconductivity.

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• Josephson scanning tunneling microscopy
• Antibunched photons from inelastic Cooper-pair tunneling
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• Self-consistent dynamics of a Josephson junction in presence of an arbitrary environment

Cited by in corpus (22)

• The energy resolution function of a tunnel junction
• Topological Superconductivity in Skyrmion Lattices
• Scanning Josephson spectroscopy on the atomic scale
• A strongly inhomogeneous superfluid in an iron-based superconductor
• Microwave-assisted tunneling and interference effects in superconducting junctions under fast driving signals
• Superconducting Quantum Interference at the Atomic Scale
• Dynamical Coulomb Blockade as a Local Probe for Quantum Transport
• Realizing Topological Superconductivity in Tunable Bose-Fermi Mixtures with Transition Metal Dichalcogenide Heterostructures
• A millikelvin scanning tunneling microscope in ultra-high vacuum with adiabatic demagnetization refrigeration
• Combining Electron Spin Resonance Spectroscopy with Scanning Tunneling Microscopy at High Magnetic Fields
• Imaging the Spatial Form of a Superconducting Order Parameter via Josephson Scanning Tunneling Spectroscopy
• Single Channel Josephson Effect in a High Transmission Atomic Contact
• Josephson Scanning Tunneling Spectroscopy in $d_{x^2-y^2}$-wave superconductors: a probe for the nature of the pseudo-gap in the cuprate superconductors
• Quantum Brownian motion at strong dissipation probed by superconducting tunnel junctions
• How cold is the junction of a millikelvin scanning tunnelling microscope?
• An ultrahigh-vacuum cryostat for simultaneous scanning tunneling microscopy and magneto-transport measurements down to 400mK
• Time-resolved statistics of photon pairs in two-cavity Josephson photonics
• Statistical detection of Josephson, Andreev, and single quasiparticle currents in scanning tunneling microscopy
• The feedback driven atomic scale Josephson microscope
• Spin-dependent tunneling between individual superconducting bound states
• Detecting and Distinguishing Majorana Zero Modes with the Scanning Tunneling Microscope
• Josephson spectroscopy study of kagome superconductors toward the deep point-contact regime