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For the measurement of very small magnetic fields, systems based on superconducting quantum-interference devices (SQUIDs) have been manufactured and employed for many years. In liquid helium operated systems with niobium SQUIDs, wire wound gradiometers can be coupled to a shielded SQUID, but in ceramic high-temperature superconductors (HTS) this is not a common setup, since appropriate thin HTS wires with a bending radius of millimeters operating at liquid nitrogen temperature and the corresponding joining technology is not easily available. We investigated the potential of additive manufacturing to fabricate hybrid plastic and ceramic structures of the insulating perovskite SrTiO3 together with the high- Tc superconductor YBa2Cu3O7, reaching a $T_{c}$ of up to 84 K in the 3D-printed polycrystalline materials. With our measurement setup, the structures are characterized in terms of $T_{c}$ and $I_{c}$ . With the successful process, now larger sample sizes and arbitrary hybrid structures can be manufactured. A gradiometric pick-up loop was fabricated and characterized. These structures can be integrated in low-noise plastic holders and encapsulated by plastic-printed capsules to protect the HTS devices from humidity. By additive manufacturing very versatile ceramic HTS multimaterial hybrid modules can be employed for novel HTS SQUID systems.

UV-light emitting diodes (395–278 nm) were used to investigate the gas sensing attributes of planar and nanostructured ZnO/AlN thin films on Si substrate towards NO2 at room temperature. A significant increased sensitivity ((Rg − Ra)/Ra = 65.3 ppm NO2 in air) and a strong reduction in recovery time (Trec = 14 min) were already observed for the planar ZnO/AlN thin films under UV-B (305 nm) irradiation compared to the other UV wavelengths, while the device showed no obvious response in dark. By enlarging the surface-to-volume ratio of the sensors (i.e., creating nanostructured ZnO/AlN thin films), an increased response time is expected to be observed.