Superfluidity is a manifestation of the operation of the laws of quantum mechanics on a macroscopic scale. The conditions under which superfluidity becomes manifest have been extensively explored experimentally in both quantum liquids (liquid 4 He being the canonical example) and ultracold atomic gases, including as a function of dimensionality. Of particular interest is the hitherto unresolved question of whether a solid can be superfluid.

As a high-kappa superconductor with a coherence length of 7 nm, the superconductor Nb3Sn is highly susceptible to material features at the sub-micron scale. For niobium surfaces coated with a thin layer of Nb3Sn using the vapour diffusion method, the polycrystalline nature of the film grown lends to the possibility that performance-degrading nonuniformities may develop. In particular, regions of insufficiently thick coating and tin-depletion have been seen to occur in sample coupons.

Tiger beetles pursue prey by adjusting their heading according to a time-delayed proportional control law that minimizes the error angle (Haselsteiner et al 2014 J. R. Soc. Interface 11 20140216). This control law can be further interpreted in terms of mechanical actuation: to catch prey, tiger beetles exert a sideways force by biasing their tripod gait in proportion to the error angle measured half a stride earlier. The proportional gain was found to be nearly optimal in the sense that it minimizes the time to point directly toward the prey.

Developing critical thinking skills is a common goal of an undergraduate physics curriculum. How do students make sense of evidence and what do they do with it? In this study, we evaluated students' critical thinking behaviors through their written notebooks in an introductory physics laboratory course. We compared student behaviors in the Structured Quantitative Inquiry Labs (SQILabs) curriculum to a control group and evaluated the fragility of these behaviors through procedural cueing.

We extend the recently proposed heat-bath configuration interaction (HCI) method [Holmes, Tubman, Umrigar, J. Chem. Theory Comput. 2016, 12, 3674], by introducing a semistochastic algorithm for performing multireference Epstein-Nesbet perturbation theory, in order to completely eliminate the severe memory bottleneck of the original method. The proposed algorithm has several attractive features. First, there is no sign problem that plagues several quantum Monte Carlo methods.

Theoretically, it has been known that breaking spin degeneracy and effectively realizing spinless fermions is a promising path to topological superconductors. Yet, topological superconductors are rare to date. Here we propose to realize spinless fermions by splitting the spin degeneracy in momentum space. Specifically, we identify monolayer hole-doped transition metal dichalcogenide (TMD)s as candidates for topological superconductors out of such momentum-space-split spinless fermions.

We demonstrate an instrument for time-resolved magnetic imaging that is highly sensitive to the in-plane magnetization state and dynamics of thin-film bilayers of yttrium iron garnet [Y3Fe5O12(YIG)]/Pt: the time-resolved longitudinal spin Seebeck (TRLSSE) effect microscope. We detect the local in-plane magnetic orientation within the YIG by focusing a picosecond laser to generate thermally driven spin current from the YIG into the Pt by the spin Seebeck effect and then use the inverse spin Hall effect in the Pt to transduce this spin current to an output voltage.

A nanophotonic trapping platform based on on-chip tunable optical interference allows parallel processing of biomolecules and holds promise to make single molecule manipulation and precision measurements more easily and broadly available. The nanophotonic standing wave array trap (nSWAT) device [Nat. Nanotechnol. 9, 448 (2014); Nano Lett. 16, 6661 (2016)] represents such a platform and can trap a large array of beads by the evanescent field of the standing wave of a nanophotonic waveguide and reposition them using an integrated microheater.

Several charge integrating CMOS pixel front ends utilizing charge removal techniques have been fabricated to extend dynamic range for X-ray diffraction applications at synchrotron sources and X-ray free electron lasers (XFELs). The pixels described herein build on the mixed mode pixel array detector (MM-PAD) framework, developed previously by our group to perform high dynamic range imaging.

Half-filled Landau levels form a zoo of strongly correlated phases. These include non-Fermi-liquids (NFLs), fractional quantum Hall (FQH) states, nematic phases, and FQH nematic phases. This diversity begs the following question: what keeps the balance between the seemingly unrelated phases? The answer is elusive because the Halperin-Lee-Read description that offers a natural departure point is inherently strongly coupled. However, the observed nematic phases suggest that nematic fluctuations play an important role.