Jonginn Yun

Low-temperature transport measurements and analysis of nonreciprocal superconducting response in van der Waals heterostructures.

This project investigated nonreciprocal superconducting transport in a van der Waals heterostructure combining a two-dimensional superconductor with a magnetic layered material. The central physics is a magnetic-proximity-induced superconducting diode effect, where the critical supercurrent depends on current direction.

I led low-temperature transport measurements and primary data analysis, established measurement protocols and robustness checks, and contributed to interpretation and figure production for the main experimental claims. The measurements required low-noise transport techniques at cryogenic temperature, including lock-in detection, DC sourcing, nanovoltage readout, superconducting magnet operation, and careful wiring and filtering.

Scientifically, the project connects broken inversion and time-reversal symmetries to nonreciprocal critical-current behavior in a NbSe2/CrPS4-based spin-valve geometry.