We predict an inhomogeneous phase of superfluid ${}^3\mathrm{He}$ films in which translational symmetry is spontaneously broken in the plane of the film. This phase is energetically favored over a range of film thicknesses, $D_{c_2}(T)<D<D_{c_1}(T)$, separating distinct homogeneous superfluid phases. The instability at the critical film thickness, $D_{c_2}\approx 9\xi (T)$, is a single-mode instability generating striped phase order in the film. Numerical calculations of the order parameter and free energy indicate a second-order instability to a periodic lattice of degenerate $B$-like phases separated by domain walls at $D_{c_1}\approx 13\xi (T)$.

We use a pulse of surface acoustic waves (SAWs) to control the electron population and depopulation of a quantum dot. The barriers between the dot and reservoirs are set high to isolate the dot. Within a time scale of $\sim 100\mathrm{s}$ the dot can be set to a nonequilibrium charge state, where an empty (occupied) level stays below (above) the Fermi energy. A pulse containing a fixed number of SAW periods is sent through the dot, controllably changing the potential, and hence the tunneling probability, to add (remove) an electron to (from) the dot.

We demonstrate a hard-x-ray microscope that does not use a lens and is not limited to a small field of view or an object of finite size. The method does not suffer any of the physical constraints, convergence problems, or defocus ambiguities that often arise in conventional phase-retrieval diffractive imaging techniques. Calculation times are about a thousand times shorter than in current iterative algorithms. We need no a priori knowledge about the object, which can be a transmission function with both modulus and phase components. The technique has revolutionary implications for x-ray imaging of all classes of specimen.

We present an experiment where a single molecule strongly affects the amplitude and phase of a laser field emerging from a subwavelength aperture. We achieve a visibility of $-6\%$ in direct and $+10\%$ in cross-polarized detection schemes. Our analysis shows that a close to full extinction should be possible using near-field excitation.

We present measurements of the time-dependent $CP$-violation parameters $S$ and $C$ in $B^0\to {\eta }^{\prime }{K}^0$ decays. The data sample corresponds to $384\times {10}^6$ $B\overline{B}$ pairs produced by $e^{+}{e}^{-}$ annihilation at the ${\rm Y}(4S)$. The results are $S=0.58\pm 0.10\pm 0.03$ and $C=-0.16\pm 0.07\pm 0.03$. We observe mixing-induced $CP$ violation with a significance of 5.5 standard deviations in this $b\to s$ penguin dominated mode.

We present improved measurements of $CP$-violation parameters in $B^0\to \varphi K^0$, ${\eta }^{\prime }{K}^0$, $K_S^0{K}_S^0{K}_S^0$ decays based on a sample of $535\times {10}^6$ $B\overline{B}$ pairs collected at the ${\rm Y}(4S)$ resonance with the Belle detector at the KEKB energy-asymmetric $e^{+}{e}^{-}$ collider. We obtain $\sin 2{\varphi }_1^{\mathrm{eff}}=+0.64\pm 0.10(\mathrm{stat})\pm 0.04(\mathrm{syst})$ for $B^0\to {\eta }^{\prime }{K}^0$, $+0.50\pm 0.21(\mathrm{stat})\pm 0.06(\mathrm{syst})$ for $B^0\to \varphi K^0$, and $+0.30\pm 0.32(\mathrm{stat})\pm 0.08(\mathrm{syst})$ for $B^0\to K_S^0{K}_S^0{K}_S^0$ decays. We have observed $CP$ violation in the $B^0\to {\eta }^{\prime }{K}^0$ decay with a significance of 5.6 standard deviations. We also perform an improved measurement of $CP$ asymmetries in $B^0\to J/\psi K^0$ decays and obtain $\sin 2{\varphi }_1=+0.642\pm 0.031(\mathrm{stat})\pm 0.017(\mathrm{syst})$.

We propose a cyclic refrigeration principle based on mesoscopic electron transport. Synchronous sequential tunneling of electrons in a Coulomb-blockaded device, a normal metal-superconductor single-electron box, results in a cooling power of $\sim k_{B}T\times f$ at temperature $T$ over a wide range of cycle frequencies $f$. Electrostatic work, done by the gate voltage source, removes heat from the Coulomb island with an efficiency of $\sim k_{B}T/\Delta$, where $\Delta$ is the superconducting gap parameter. The performance is not affected significantly by nonidealities, for instance by offset charges. We propose ways of characterizing the system and of its practical implementation.

Our sense of smell relies on sensitive, selective atomic-scale processes that occur when a scent molecule meets specific receptors in the nose. The physical mechanisms of detection are unclear: odorant shape and size are important, but experiment shows them insufficient. One novel proposal suggests receptors are actuated by inelastic electron tunneling from a donor to an acceptor mediated by the odorant, and provides critical discrimination. We test the physical viability of this mechanism using a simple but general model. With parameter values appropriate for biomolecular systems, we find the proposal consistent both with the underlying physics and with observed features of smell. This mechanism suggests a distinct paradigm for selective molecular interactions at receptors (the swipe card model): recognition and actuation involve size and shape, but also exploit other processes.

We describe measurement and interpretation of the force acting on a smooth hydrophilic glass particle during rapid ($1–100\mu \mathrm{m}{\mathrm{s}}^{-1}$) approach to, and separation from, a hydrophilic glass plate in viscous concentrated aqueous sucrose solutions ($0.001\mathrm{Pa}\mathrm{s}<\eta <0.090\mathrm{Pa}\mathrm{s}$). We find that the force is accurately described by Reynolds lubrication theory with a no-slip boundary condition, even at maximum strain rates of up to $250000{\mathrm{s}}^{-1}$. Compared to earlier studies of hydrodynamic forces on small particles, we reduce the uncertainty in the absolute particle-plate separation by using an evanescent-wave measurement of the separation.

The doping characteristics and carrier transport in a GaAs $p\mathrm{\text{−}}n$ junction were visualized with a $\sim 10\mathrm{nm}$ spatial resolution, using light-modulated scanning tunneling spectroscopy. The dynamics of minority carriers under operating conditions, such as recombination, diffusion, and electric field induced drift, which had previously been analyzed on the basis of empirical electric properties, were successfully examined on the nanoscale. These results provide a solid basis for elucidating the mechanism of the carrier transport properties predicted by using the macroscopic analysis.

Based on temperature dependent far infrared transmission spectra of ${\mathrm{YMn}}_2{\mathrm{O}}_5$ and ${\mathrm{TbMn}}_2{\mathrm{O}}_5$ single crystals, we report the observation of electric dipole-active magnetic excitations, or electromagnons, in these multiferroics. Electromagnons are found to be directly responsible for the steplike anomaly of the static dielectric constant at the commensurate—incommensurate magnetic transition and are the origin of the colossal magneto-dielectric effect reported in these multiferroics.

How important is fast measurement for fault-tolerant quantum computation? Using a combination of existing and new ideas, we argue that measurement times as long as even 1000 gate times or more have a very minimal effect on the quantum accuracy threshold. This shows that slow measurement, which appears to be unavoidable in many implementations of quantum computing, poses no essential obstacle to scalability.

We conducted three torsion-balance experiments to test the gravitational inverse-square law at separations between 9.53 mm and $55\mu \mathrm{m}$, probing distances less than the dark-energy length scale ${\lambda }_d=\sqrt[4]{\hslash c/{\rho }_d}\approx 85\mu \mathrm{m}$. We find with 95% confidence that the inverse-square law holds ($|\alpha |\le 1$) down to a length scale $\lambda =56\mu \mathrm{m}$ and that an extra dimension must have a size $R\le 44\mu \mathrm{m}$.

Unlike the $\mathrm{Si}\mathrm{\text{−}}{\mathrm{SiO}}_2$ interface, the $\mathrm{SiC}\mathrm{\text{−}}{\mathrm{SiO}}_2$ interface has large defect densities. Though nitridation has been shown to reduce the defect density, the effect of H remains an open issue. Here we combine experimental data and the results of first-principles calculations to demonstrate that a Si-C-O bonded interlayer with correlated threefold-coordinated C atoms accounts for the observed defect states, for passivation by N and atomic H, and for the nature of residual defects.

We report on the successful terahertz emission (0.6–1 THz) that is continuous and tunable in its frequency and power, by driving Josephson vortices in resonance with the collective standing Josephson plasma modes excited in stacked ${\mathrm{Bi}}_2{\mathrm{Sr}}_2{\mathrm{CaCu}}_2{\mathrm{O}}_{8+x}$ intrinsic Josephson junctions. Shapiro-step detection was employed to confirm the terahertz-wave emission. Our results provide a strong feasibility of developing long-sought solid-state terahertz-wave emission devices.

A new frontier of discrete-line $\gamma$-ray spectroscopy at ultrahigh spin has been opened in the rare-earth nuclei ${}^{157,158}\mathrm{Er}$. Four rotational structures, displaying high moments of inertia, have been identified, which extend up to spin $\sim 65\hslash$ and bypass the band-terminating states in these nuclei which occur at $\sim 45\hslash$. Cranked Nilsson-Strutinsky calculations suggest that these structures arise from well-deformed triaxial configurations that lie in a valley of favored shell energy which also includes the triaxial strongly deformed bands in ${}^{161–167}\mathrm{Lu}$.

It is possible to achieve an arbitrary amount of entanglement between two atoms using only spontaneously emitted photons, linear optics, single-photon sources, and projective measurements. This is in contrast to all current experimental proposals for entangling two atoms, which are fundamentally restricted to one entanglement bit or “ebit.”

We propose that the inversion symmetry of the graphene honeycomb lattice is spontaneously broken via a magnetic-field-dependent Peierls distortion. This leads to valley splitting of the $n=0$ Landau level but not of the other Landau levels. Compared to quantum Hall valley ferromagnetism recently discussed in the literature, lattice distortion provides an alternative explanation to all of the currently observed quantum Hall plateaus in graphene.

We observed an oscillatory behavior, both in space and time, of the induction in ${\mathrm{Bi}}_2{\mathrm{Sr}}_2{\mathrm{CaCu}}_2{\mathrm{O}}_{8+\delta }$ crystals exposed to a steady magnetic field. This new “flux waves” phenomenon appears near the order-disorder vortex phase transition, under specific conditions of temperature and induction gradient. A theoretical description of this effect is based on two coupled equations: the Landau-Khalatnikov dynamic equation for the order parameter of the vortex phase transition and the diffusion equation for the time evolution of the magnetic induction. A linear stability analysis of these equations predicts an oscillatory instability characterized by a period and wavelength in accordance with the experimental results.

The statistics of the relaminarization of localized turbulence in a pipe are examined by direct numerical simulation. As in recent experimental data [J. Peixinho and T. Mullin, Phys. Rev. Lett. 96, 094501 (2006)], the half-life for the decaying turbulence is consistent with the scaling $({\mathrm{Re}}_c-\mathrm{Re}{)}^{-1}$, indicating a boundary crisis of the localized turbulent state familiar in low-dimensional dynamical systems. The crisis Reynolds number is estimated as ${\mathrm{Re}}_c=1870$, a value within 7% of the experimental value 1750. We argue that the frequently asked question, of which initial disturbances at a given Re trigger sustained turbulence in a pipe, is really two separate questions: the “local phase space” question (local to the laminar state) of what threshold disturbance at a given Re is needed to initially trigger turbulence, followed by the “global phase space” question of whether Re exceeds ${\mathrm{Re}}_c$ at which point the turbulent state becomes an attractor.