Controlling magnon densities in magnetic materials enables driving spin transport in magnonic devices. We demonstrate the creation of large, out-of-equilibrium magnon densities in a thin-film magnetic insulator via microwave excitation of coherent spin waves and subsequent multimagnon scattering. We image both the coherent spin waves and the resulting incoherent magnon gas using scanning-probe magnetometry based on electron spins in diamond. We find that the gas extends unidirectionally over hundreds of micrometers from the excitation stripline. Surprisingly, the gas density far exceeds that expected for a boson system following a Bose-Einstein distribution with a maximum value of the chemical potential. We characterize the momentum distribution of the gas by measuring the nanoscale spatial decay of the magnetic stray fields. Our results show that driving coherent spin waves leads to a strong out-of-equilibrium occupation of the spin-wave band, opening new possibilities for controlling spin transport and magnetic dynamics in target directions.

Diamond membrane devices containing optically coherent nitrogen-vacancy (NV) centers are key to enable novel cryogenic experiments such as optical ground-state cooling of hybrid spin-mechanical systems and efficient entanglement distribution in quantum networks. Here, we report on the fabrication of a (3.4 ± 0.2) μm thin, smooth (surface roughness r_q < 0.4 nm over an area of 20 μm by 30 μm) diamond membrane containing individually resolvable, narrow linewidth (< 100 MHz) NV centers. We fabricate this sample via a combination of high-energy electron irradiation, high-temperature annealing, and an optimized etching sequence found via a systematic study of the diamond surface evolution on the microscopic level in different etch chemistries. Although our particular device dimensions are optimized for cavity-enhanced entanglement generation between distant NV centers in open, tunable microcavities, our results have implications for a broad range of quantum experiments that require the combination of narrow optical transitions and micrometer-scale device geometry.

An understanding of the paleoenvironment and the main sedimentary processes behind preserved deposits is crucial to correctly interpret and represent lithofacies and facies associations in geomodels that are used in the hydrocarbon industry, particularly when a limited dataset of cores is available. In this paper a fairly common facies association is discussed containing massive sands - here defined as thick (>0.5 m) structureless sand beds devoid of primary sedimentary structures, or with some faint lamination - deposited by mass failures of channel banks in deep fluvial and estuarine channels. Amongst geologists it is generally accepted that liquefaction is the main trigger of large bank failures in sandy subaqueous slopes. However, evidence is mounting that for sand deposits a slow, retrogressive failure mechanism of a steep subaqueous slope, known as breaching, is the dominant process. A model of breaching-induced turbidity current erosion and sedimentation is presented that explains the presence of sheet-like massive sands and channel-like massive sands and the sedimentary structures of the related deposits. Sheet-like packages of spaced planar lamination that are found together with massive sand bodies in deposits of these environments are identified as proximal depositional elements of breach failure events. The model, acquired from sedimentary structures in deposits in the Eocene estuarine Vlierzele Sands, Belgium, is applied to outcrops of the Dinantian fluvial Fell Sandstone, England, and cores of the Tilje and Nansen fms (Lower Jurassic, Norwegian Continental Shelf). The possible breach failure origin of some other massive sands described in literature from various ancient shallow water environments is discussed. Breach failure generated massive sands possibly also form in deep marine settings. The potentially thick and homogeneous, well-sorted sand deposits bear good properties for hydrocarbon flow when found in such an environment. However, in case of deposition in an estuarine or fluvial channel, these sand bodies are spatially constricted and careful facies interpretation is key to identifying this. When constructing a static reservoir model, this needs to be considered both for in-place volume calculations as well as drainage strategies.

Particle defects are important contributors to yield loss in semi-conductor manufacturing. Particles need to be detected and characterized in order to determine and eliminate their root cause. We have conceived a process flow for advanced defect classification (ADC) that distinguishes three consecutive steps; detection, review and classification. For defect detection, TNO has developed the Rapid Nano (RN3) particle scanner, which illuminates the sample from nine azimuth angles. The RN3 is capable of detecting 42 nm Latex Sphere Equivalent (LSE) particles on XXX-flat Silicon wafers. For each sample, the lower detection limit (LDL) can be verified by an analysis of the speckle signal, which originates from the surface roughness of the substrate. In detection-mode (RN3.1), the signal from all illumination angles is added. In review-mode (RN3.9), the signals from all nine arms are recorded individually and analyzed in order to retrieve additional information on the shape and size of deep sub-wavelength defects. This paper presents experimental and modelling results on the extraction of shape information from the RN3.9 multi-azimuth signal such as aspect ratio, skewness, and orientation of test defects. Both modeling and experimental work confirm that the RN3.9 signal contains detailed defect shape information. After review by RN3.9, defects are coarsely classified, yielding a purified Defect-of-Interest (DoI) list for further analysis on slower metrology tools, such as SEM, AFM or HIM, that provide more detailed review data and further classification. Purifying the DoI list via optical metrology with RN3.9 will make inspection time on slower review tools more efficient.