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arXiv · 2411.13355

Phase-Biased Andreev Diffraction Grating

Magnus R. Lykkegaard·Anders Enevold Dahl·Karsten Flensberg·Tyler Lindemann·Michael J. Manfra·Charles M. Marcus
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Abstract

In optical diffraction, the phase difference between sources in a grating or multi-slit mask is determined by the angle to the imaging screen, yielding the familiar multi-lobed diffraction image. Here, we realize a similar phenomenon in a superconductor-semiconductor hybrid circuit configured to allow Andreev scattering from multiple parallel scatterers. Phase differences between scatterers are set by tapping off of a remote superconducting meander. We investigate arrays with two, three, four, and ten Andreev scatterers, examining local and nonlocal diffraction patterns, finding good agreement with a theory of multiple Andreev scattering, not to be confused with multiple Andreev reflection. Adding current-carrying taps to the meander allows individual phase control.

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Magnus R. Lykkegaard, Anders Enevold Dahl, Karsten Flensberg, Tyler Lindemann, Michael J. Manfra, Charles M. Marcus. 2024-11-20. Phase-Biased Andreev Diffraction Grating. https://doi.org/10.1103/d4kk-sgmh

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