High‐temperature superconductors (HTSs) are important for potential applications and for understanding the origin of strong correlations. Bi2Sr2CaCu2O8+δ (BSCCO), a van der Waals material, offers a platform to probe the physics down to a unit‐cell. Guiding the flow of electrons by patterning 2DEGS and oxide heterostructures has brought new functionality and access to new science. Similarly, modifying superconductivity in HTS locally, on a small length scale, is of immense interest for superconducting electronics. A route to modify superconductivity locally by depositing metal on the surface is reported here by transport studies on few unit‐cell thick BSCCO. Deposition of chromium (Cr) on the surface over a selected area of BSCCO results in insulating behavior of the underlying region. Cr locally depletes oxygen in CuO2 planes and disrupts the superconductivity in the layers below. This technique of modifying superconductivity is suitable for making sub‐micrometer superconducting wires and more complex superconducting devices.

In this work, we demonstrate a simple technique to grow high-quality whiskers of Bi2 Sr2 CaCu2 O8+δ – a high Tc superconductor. Structural analysis shows the single-crystalline nature of the grown whiskers. To probe electrical properties, we exfoliate these whiskers into thin flakes (~50 nm thick) using the scotch-tape technique and develop a process to realize good electrical contacts. We observe a superconducting critical temperature, Tc, of 86 K. We map the evolution of the critical current as a function of temperature. With 2-D materials emerging as an exciting platform to study low-dimensional physics, our work paves the way for future studies on two-dimensional high-Tc superconductivity.

Superconducting nanowires are very important due to their applications ranging from quantum technology to astronomy. In this work, we implement a non-invasive process to fabricate nanowires of high-Tc superconductor Bi2Sr2CaCu2O8+δ (BSCCO). We demonstrate that our nanowires can be used as bolometers in the visible range with very high responsivity of 9.7 × 103 V/W. Interestingly, in a long (30 μm) nanowire of 9 nm thickness and 700 nm width, we observe bias current dependent localized spots of maximum photovoltage. Moreover, the scalability of the bolometer responsivity with the normal state resistance of the nanowire could allow further performance improvement by increasing the nanowire length in a meander geometry. We observe phase slip events in nanowires with small cross-sections (12 nm thick, 300 nm wide, and 3μm long) at low temperatures. Our study presents a scalable method for realizing sensitive bolometers working near the liquid-nitrogen temperature.

We present systematic measurements of the mechanical properties of few unit cell (UC) thick exfoliated crystals of a high-Tc cuprate superconductor Bi2Sr2CaCu2O8+δ. We determine the elastic properties of these crystals by deformation using an atomic force microscope at room temperature. With the spatial measurements of local compliance and their detailed modeling, we independently determine the Young's modulus of rigidity and the prestress. The Young's modulus of rigidity is found to be in the range of 22 GPa–30 GPa for flakes with a thickness from ∼5 UC to 18 UC. The prestress spreads over the range of 5 MPa–46 MPa, indicating a run-to-run variation during the exfoliation process. The determination of Young's modulus of rigidity for thin flakes is further verified from the recently reported buckling technique.