Prof. Sang-Hyun Oh and Prof. Randall Victora in a collaboration with faculty and researchers from the Dept. of Biomedical Engineering and the Dept. of Physics at UMN, and from Imperial College in London introduce a technique called template stripping to create ultra-sharp pyramids and wedges. The technique, presented in a paper titled “Template-Stripped Multifunctional Wedge and Pyramid Arrays for Magnetic Nanofocusing and Optical Sensing,” can create tips as small as 10 nm in radius. These unusually sharp tips can concentrate both magnetic and optical fields, which allows for rapid trapping of magnetic nanoparticles followed by optical detection. The technique has important implications for the design and fabrication of devices with broad applications in biosensing, nano-optics, and spintronics.