Geometric Scaling of the Current-Phase Relation of Niobium Nano-Bridge Junctions
arXiv:2308.00932 · doi:10.1021/acsnano.3c01301
Abstract
The nano-bridge junction (NBJ) is a type of Josephson junction that is advantageous for the miniaturization of superconducting circuits. However, the current-phase relation (CPR) of the NBJ usually deviates from a sinusoidal function which has been explained by a simplified model with correlation only to its effective length. Here, we investigated both measured and calculated CPRs of niobium NBJs of a cuboidal shape with a three-dimensional bank structure. From a sine-wave to a saw-tooth-like form, we showed that deviated CPRs of NBJs can be described quantitatively by its skewness Δθ. Furthermore, the measured dependency of Δθ on the critical current {I_0} from 108 NBJs turned out to be consistent with the calculated ones derived from the change in geometric dimensions. It suggested that the CPRs of NBJs can be tuned by their geometric dimensions. In addition, the calculated scaling behavior of Δθ versus {I_0} in three-dimensional space was provided for the future design of superconducting circuits of a high integration level by using niobium NBJs.
20 pages, 10 figures
References in corpus (5)
- SQUID-on-tip with single-electron spin sensitivity for high-field and ultra-low temperature nanomagnetic imaging
- A high performance Nb nano-SQUID with a three-dimensional structure
- On-chip SQUID measurements in the presence of high magnetic fields
- 3D nano-bridge-based SQUID susceptometers for scanning magnetic imaging of quantum materials
- Miniaturization of the Superconducting Memory Cell via a Three-Dimensional Nb Nano-Superconducting Quantum Interference Device