Josephson junctions made with conventional s-wave superconductors and containing multiple layers of ferromagnetic materials can carry spin-triplet supercurrent in the presence of certain types of magnetic inhomogeneity. In junctions containing three ferromagnetic layers, the triplet supercurrent is predicted to be maximal when the magnetizations of adjacent layers are orthogonal, and zero when the magnetizations of any two adjacent layers are parallel. Here we demonstrate on-off control of the spin-triplet supercurrent in such junctions, achieved by rotating the magnetization direction of one of the three layers by 90 • . We obtain "on-off" ratios of 5, 7, and 19 for the supercurrent in the three samples studied so far. These observations directly confirm one of the most salient predictions of the theory, and pave the way for applications of spin-triplet Josephson junctions in the nascent area of "superconducting spintronics."

Recently, there have been several national calls to emphasize physics practices and skills within laboratory courses. In this paper, we describe the redesign and implementation of a two-course sequence of algebra-based physics laboratories at Michigan State University called Design Analysis Tools and Apprenticeship (DATA) Lab. The large-scale course transformation removes physics specific content from the overall learning goals of the course, and instead, uses physics concepts to focus on specific laboratory practices and research skills that students can take into their future careers. Students in DATA Lab engage in the exploration of physical systems to increase their understanding of experimental process, data analysis, collaboration, and scientific communication. In order to ensure our students are making progress toward the skills outlined in the course learning goals, we designed all of the assessments in the courses to evaluate their progress specific to these laboratory practices. Here, we will describe the structures, scaffolds, goals, and assessments of the course.

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We report on a two-step technique for post-bond III-V substrate removal involving precision mechanical milling and selective chemical etching. We show results on GaAs, GaSb, InP, and InAs substrates and from mm-scale chips to wafers.

Low loss silicon nitride ring resonator reflectors provide feedback to a III/V gain chip, achieving single-mode lasing at 772nm. The Si3N4 is fabricated in a CMOS foundry compatible process that achieves loss values of 0.036dB/cm.