Alv Skarpeid

• Strand, Frode Sneve; Cooil, Simon Phillip; Campbell, Quinn T.; Flounders, John J.; Røst, Håkon & Åsland, Anna Cecilie [Vis alle 16 forfattere av denne artikkelen] (2025). Direct Observation of 2DEG States in Shallow Si:Sb δ-Layers. Journal of Physical Chemistry C. ISSN 1932-7447. 129(2), s. 1339–1347. doi: 10.1021/acs.jpcc.4c07331. Fulltekst i vitenarkiv Vis sammendrag

  We investigate the electronic structure of high-density layers of Sb dopants in a silicon host, so-called Si:Sb δ-layers. We show that, in spite of the known challenges in producing highly confined Sb δ-layers, sufficient confinement is created such that the lowest conduction band states (Γ states, studied in depth in other silicon δ-layers), become occupied and can be observed using angle-resolved photoemission spectroscopy. The electronic structure of the Si:Sb δ-layers closely resembles that of Si:P systems, where the observed conduction band is near-parabolic and slightly anisotropic in the k∥ plane. The observed Γ state extends ∼1 nm in the out-of-plane direction, which is slightly wider than the 1/3 monolayer thick dopant distribution. This is caused by a small segregation of the dopant layer, which is nevertheless minimal when comparing with earlier published attempts. Our results serve to demonstrate that Sb is still a feasible dopant alternative for use in the semiconductor δ-layer platform, providing similar electronic functionality to Si:P systems. Additionally, it has the advantages of being less expensive, more controllable, safer to handle, and more compatible with industrial patterning techniques. Si:Sb is therefore a viable platform for emerging quantum device applications.

• Skarpeid, Alv Johan; Hugdal, Henning Goa; Salamone, Tancredi; Amundsen, Morten & Jacobsen, Sol Hernæs (2024). Non-constant geometric curvature for tailored spin-orbit coupling and chirality in superconductor-magnet heterostructures. Journal of Physics: Condensed Matter. ISSN 0953-8984. 36(23). doi: 10.1088/1361-648X/ad2e23. Fulltekst i vitenarkiv Vis sammendrag

  We show that tailoring the geometric curvature profile of magnets can be used for bespoke design of an effective non-relativistic spin–orbit coupling, which may be used to control proximity effects if the magnet is coupled to a superconductor. We consider proximity-coupled one-dimensional magnetic wires with variable curvatures, specifically three distinct shapes classified as J-, C-, and S-type. We demonstrate a chirality-dependent spin polarization of the superconducting correlations, and show the role of curvature in determining the ground state of mixed-chirality junctions. We speculate on how this may be implemented in novel device design, and include analysis of its usage in a spin-triplet SQUID.

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• Schenk, Richard Justin; Skarpeid, Alv; Røst, Håkon; Yadav, Rohit; Cooil, Simon Phillip & Wells, Justin William (2026). Modifying the Electronic Structure of Nickel with Antimony Surface Alloys. Fulltekst i vitenarkiv
• Stalsberg, Marte Pedersen; Strand, Frode Sneve; Cooil, Simon Phillip; Campbell, Quinn T.; Flounders, John J. & Røst, Håkon Ivarssønn [Vis alle 10 forfattere av denne artikkelen] (2024). A 2D electron gas by shallow Sb doping in Si for use in Quantum Devices. Fulltekst i vitenarkiv
• Stalsberg, Marte Pedersen; Strand, Frode Sneve; Cooil, Simon Phillip; Campbell, Quinn T.; Flounders, John J. & Røst, Håkon Ivarssønn [Vis alle 10 forfattere av denne artikkelen] (2023). Atomically Sharp and High-Density Sb Doping in Si for use in Quantum Devices. Fulltekst i vitenarkiv

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