We describe the unusual properties of γ-SnSe, a new orthorhombic binary phase in the tin monoselenide system. This phase exhibits an ultranarrow band gap under standard pressure and temperature conditions, leading to high conductivity under ambient conditions. Density functional calculations identified the similarity and difference between the new γ-SnSe phase and the conventional α-SnSe based on the electron localization function. Very good agreement was obtained for the band gap width between the band structure calculations and the experiment, and insight provided for the mechanism of reduction in the band gap. The unique properties of this material may render it useful for applications such as thermal imaging devices and solar cells.

We perform low-temperature magneto-conductance measurements on Cu and Au thin films with adsorbed chiral molecules and investigate their phase-coherent transport properties. Upon adsorption of chiral molecules, the spin−orbit coupling strength in Cu decreases and the Au films become ferromagnetic as evident from weak localization and antilocalization data. A theoretical model indicates that anisotropy in the molecular tilt angles, provided that the chiral molecules act as magnetic moments, induces a nonvanishing magnetic exchange interaction, causing changes in the spin−orbit coupling strength in Cu and Au. Our work adds a new viewpoint to the plethora of unique phenomena emerging from chiral molecule adsorption on materials.

Unconventional superconductivity was realized in systems comprising a monolayer of magnetic adatoms adsorbed on conventional superconductors, forming Shiba‐bands. Another approach to induce unconventional superconductivity and 2D Shiba‐bands was recently introduced, namely, by adsorbing chiral molecules (ChMs) on conventional superconductors, which act in a similar way to magnetic impurities as verified by conductance spectroscopy. However, the fundamental effect ChMs have on the strength of superconductivity has not yet been directly observed and mapped. In this work, local magnetic susceptometry is applied on heterostructures comprising islands of ChMs (α‐helix L‐polyalanine) monolayers adsorbed on Nb. It is found that the ChMs alter the superconducting landscape, resulting in spatially‐modulated weaker superconductivity. Surprisingly, the reduced diamagnetic response is located along the perimeter of the islands with respect to both their interior and the bare Nb. The authors suggest that topological edge‐states forming at the edges are the source of the reduced superconductivity, akin to the case of magnetic islands. The results pave new paths for the realization of topological‐superconductivity‐based devices with changing order parameter.

We investigate the voltage-current characteristics of a superconductor-insulator-ferromagnet heterostructure, where the insulating layer contains pinhole-defects. The superconducting layer exhibits multiple voltage jumps that are hysteretic with the current sweep direction. This characteristic of the resistive state is due to pinholes that induce local, distinct, coupling regions between the superconducting and ferromagnetic layers which may generate phase-slip lines or vortex channeling. These findings point to a magnetically driven design of a superconductor memristor. Concomitantly, the junctions display both absolute and differential negative resistances below the superconducting critical temperature and current. This anomalous behavior is analyzed using a circuit approach and is attributed to current passing through pinholes within the insulating layer. These two unique pinhole-related effects can be applied in superconductor-based switches and memory devices.