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The Space Weather Atmospheric Reconfigurable Multiscale Experiment (SWARM-EX) is a National Science Foundation (NSF) sponsored CubeSat mission distributed across six colleges and universities in the United States. The project has three primary goals: (1) contributing to aeronomy and space weather knowledge, (2) demonstrating novel engineering technology, and (3) advancing higher education. The scientific focus of SWARM-EX is to study the spatial and temporal variability of ion-neutral interactions in the equatorial Ionosphere-Thermosphere (I-T) region. Since the mission consists of three spacecraft operating in a swarm, SWARM-EX will take in-situ measurements of the neutral and ion composition on timescales of less than an orbital period to study the persistence and correlation between different phenomena in the I-T region. The engineering objectives of SWARM-EX are focused on advancing the state of the art in spacecraft formation flying. In addition to being the first passively safe, autonomous formation of more than two spacecraft, SWARM-EX will demonstrate several other key innovations. These include a novel hybrid propulsive/differential drag control scheme and the realization of a distributed aeronomy sensor. As a project selected by the NSF for its broader impacts as well as its intellectual merit, SWARM-EX aims to use CubeSat development as a vehicle for education. The six collaborating institutions have varying levels of CubeSat experience and involve students who range from first-year undergraduates to Ph.D. candidates. These differences in knowledge, as well as the distributed nature of the program, present a tremendous educational opportunity, but also raise challenges such as cross-institutional communication and coordination, document sharing and file management, and hardware development. By detailing its procedures for overcoming these challenges, the SWARM-EX team believes that it may serve as a case study for the coordination of a successful CubeSat program distributed across multiple institutions. 

In integrated photonics, specific wavelengths such as 1,550 nm are preferred due to low-loss transmission and the availability of optical gain in this spectral region. For chip-based photodetectors, two-dimensional materials bear scientifically and technologically relevant properties such as electrostatic tunability and strong light–matter interactions. However, no efficient photodetector in the telecommunication C-band has been realized with two-dimensional transition metal dichalcogenide materials due to their large optical bandgaps. Here we demonstrate a MoTe2-based photodetector featuring a strong photoresponse (responsivity 0.5 A W–1) operating at 1,550 nm in silicon photonics enabled by strain engineering the two-dimensional material. Non-planarized waveguide structures show a bandgap modulation of 0.2 eV, resulting in a large photoresponse in an otherwise photoinactive medium when unstrained. Unlike graphene-based photodetectors that rely on a gapless band structure, this photodetector shows an approximately 100-fold reduction in dark current, enabling an efficient noise-equivalent power of 90 pW Hz–0.5. Such a strain-engineered integrated photodetector provides new opportunities for integrated optoelectronic systems. 

Abstract A multi-TeV muon collider offers a spectacular opportunity in the direct exploration of the energy frontier. Offering a combination of unprecedented energy collisions in a comparatively clean leptonic environment, a high energy muon collider has the unique potential to provide both precision measurements and the highest energy reach in one machine that cannot be paralleled by any currently available technology. The topic generated a lot of excitement in Snowmass meetings and continues to attract a large number of supporters, including many from the early career community. In light of this very strong interest within the US particle physics community, Snowmass Energy, Theory and Accelerator Frontiers created a cross-frontier Muon Collider Forum in November of 2020. The Forum has been meeting on a monthly basis and organized several topical workshops dedicated to physics, accelerator technology, and detector R&D. Findings of the Forum are summarized in this report.