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The phenomenon of non-reciprocal critical current in a Josephson device, termed the Josephson diode effect, has garnered much recent interest. Realization of the diode effect requires inversion symmetry breaking, typically obtained by spin-orbit interactions. Here we report observation of the Josephson diode effect in a three-terminal Josephson device based upon an InAs quantum well two-dimensional electron gas proximitized by an epitaxial aluminum superconducting layer. We demonstrate that the diode efficiency in our devices can be tuned by a small out-of-plane magnetic field or by electrostatic gating. We show that the Josephson diode effect in these devices is a consequence of the artificial realization of a current-phase relation that contains higher harmonics. We also show nonlinear DC intermodulation and simultaneous two-signal rectification, enabled by the multi-terminal nature of the devices. Furthermore, we show that the diode effect is an inherent property of multi-terminal Josephson devices, establishing an immediately scalable approach by which potential applications of the Josephson diode effect can be realized, agnostic to the underlying material platform. These Josephson devices may also serve as gate-tunable building blocks in designing topologically protected qubits.

The Andreev bound state spectra of multi-terminal Josephson junctions form an artificial band structure, which is predicted to host tunable topological phases under certain conditions. However, the number of conductance modes between the terminals of a multi-terminal Josephson junction must be few in order for this spectrum to be experimentally accessible. In this work, we employ a quantum point contact geometry in three-terminal Josephson devices to demonstrate independent control of conductance modes between each pair of terminals and access to the single-mode regime coexistent with the presence of superconducting coupling. These results establish a full platform on which to realize tunable Andreev bound state spectra in multi-terminal Josephson junctions.

The first assortment of achiral pentafluorosulfanylated cyclobutanes (SF₅‐CBs) are now synthetically accessible through strain‐release functionalization of [1.1.0]bicyclobutanes (BCBs) using SF₅Cl. Methods for both chloropentafluorosulfanylation and hydropentafluorosulfanylation of sulfone‐based BCBs are detailed herein, as well as proof‐of‐concept that the logic extends to tetrafluoro(aryl)sulfanylation, tetrafluoro(trifluoromethyl)sulfanylation, and three‐component pentafluorosulfanylation reactions. The methods presented enable isolation of bothsynandantiisomers of SF₅‐CBs, but we also demonstrate that this innate selectivity can be overridden in chloropentafluorosulfanylation; that is, ananti‐stereoselective variant of SF₅Cl addition across sulfone‐based BCBs can be achieved by using inexpensive copper salt additives. Considering the SF₅group and CBs have been employed individually as nonclassical bioisosteres, structural aspects of these unique SF₅‐CB “hybrid isosteres” were then contextualized using SC‐XRD. From a mechanistic standpoint, chloropentafluorosulfanylation ostensibly proceeds through a curiouspolarity mismatchaddition of electrophilic SF₅radicals to the electrophilic sites of the BCBs. Upon examining carbonyl‐containing BCBs, we also observed rare instances whereby radical addition to the 1‐position of a BCB occurs. The nature of the key C(sp³)−SF₅bond formation step – among other mechanistic features of the methods we disclose – was investigated experimentally and with DFT calculations. Lastly, we demonstrate compatibility of SF₅‐CBs with various downstream functionalizations.

Megakaryocytes are a rare population of cells that develop in the bone marrow and function to produce platelets that circulate throughout the body and form clots to stop or prevent bleeding. A major challenge in studying megakaryocyte development, and the diseases that arise from their dysfunction, is the identification, classification, and enrichment of megakaryocyte progenitor cells that are produced during hematopoiesis. Here, we present a high throughput strategy for identifying and isolating megakaryocytes and their progenitor cells from a heterogeneous population of bone marrow samples. Specifically, we couple thrombopoietin (TPO) induction, image flow cytometry, and principal component analysis (PCA) to identify and enrich for megakaryocyte progenitor cells that are capable of self-renewal and directly differentiating into mature megakaryocytes. This enrichment strategy distinguishes megakaryocyte progenitors from other lineage-committed cells in a high throughput manner. Furthermore, by using image flow cytometry with PCA, we have identified a combination of markers and characteristics that can be used to isolate megakaryocyte progenitor cells using standard flow cytometry methods. Altogether, these techniques enable the high throughput enrichment and isolation of cells in the megakaryocyte lineage and have the potential to enable rapid disease identification and diagnoses ahead of severe disease progression.