We combine the results of searches for the standard model (SM) Higgs boson based on the full CDF Run II data set obtained from $\sqrt{s}=1.96\mathrm{TeV}$ $p\overline{p}$ collisions at the Fermilab Tevatron corresponding to an integrated luminosity of $9.45{\mathrm{fb}}^{-1}$. The searches are conducted for Higgs bosons that are produced in association with a $W$ or $Z$ boson, have masses in the range $90–150\mathrm{GeV}/c^2$, and decay into $b\overline{b}$ pairs. An excess of data is present that is inconsistent with the background prediction at the level of 2.5 standard deviations (the most significant local excess is 2.7 standard deviations).

We analyzed the electrophysiological response of an isolated rod photoreceptor of Xenopus laevis under stimulation by coherent and pseudothermal light sources. Using the suction-electrode technique for single cell recordings and a fiber optics setup for light delivery allowed measurements of the major statistical characteristics of the rod response. The results indicate differences in average responses of rod cells to coherent and pseudothermal light of the same intensity and also differences in signal-to-noise ratios and second-order intensity correlation functions. These findings should be relevant for interdisciplinary studies seeking applications of quantum optics in biology.

With the advent of scanning probe microscopy techniques that involve a tip and a sample in relative motion in the contact or noncontact regime, the microscopic aspects of friction have become a major branch of research called nanotribology. A significant number of recent studies in this field have concentrated on the distinction between electronic and phononic contributions to friction. Here, we are using the combination of spin-polarized scanning tunneling microscopy and single-atom manipulation in order to move individual magnetic atoms over a magnetic template. By monitoring the spin-resolved manipulation traces and comparing them with results of Monte Carlo simulations, we are able to reveal the characteristic friction force variations resulting from the occurrence of spin friction on the atomic scale.

We introduce all-electrical cross-correlation spectroscopy of molecular number fluctuations in nanofluidic channels. Our approach is based on a pair of nanogap electrochemical transducers located downstream from each other in the channel. When liquid is driven through this device, mesoscopic fluctuations in the local density of molecules are transported along the channel. We perform a time-of-flight measurement of these fluctuations by cross-correlating current-time traces obtained at the two detectors. Thereby we are able to detect ultralow liquid flow rates below $10\mathrm{pL}/\min $. This method constitutes the electrical equivalent of fluorescence cross-correlation spectroscopy.

While there is a rigorously proven relationship about uncertainties intrinsic to any quantum system, often referred to as “Heisenberg’s uncertainty principle,” Heisenberg originally formulated his ideas in terms of a relationship between the precision of a measurement and the disturbance it must create. Although this latter relationship is not rigorously proven, it is commonly believed (and taught) as an aspect of the broader uncertainty principle. Here, we experimentally observe a violation of Heisenberg’s “measurement-disturbance relationship”, using weak measurements to characterize a quantum system before and after it interacts with a measurement apparatus. Our experiment implements a 2010 proposal of Lund and Wiseman to confirm a revised measurement-disturbance relationship derived by Ozawa in 2003. Its results have broad implications for the foundations of quantum mechanics and for practical issues in quantum measurement.

Based on the full BABAR data sample, we report improved measurements of the ratios $\mathcal{R}(D^{(*)})=\mathcal{B}(\overline{B}\to D^{(*)}{\tau }^{-}{\overline{\nu }}_{\tau })/\mathcal{B}(\overline{B}\to D^{(*)}{\ell }_{\ell }^{-}{\overline{\nu }}_{\ell })$, where $\ell$ is either $e$ or $\mu$. These ratios are sensitive to new physics contributions in the form of a charged Higgs boson. We measure $\mathcal{R}(D)=0.440\pm 0.058\pm 0.042$ and $\mathcal{R}(D^{*})=0.332\pm 0.024\pm 0.018$, which exceed the standard model expectations by $2.0\sigma$ and $2.7\sigma$, respectively. Taken together, our results disagree with these expectations at the $3.4\sigma$ level. This excess cannot be explained by a charged Higgs boson in the type II two-Higgs-doublet model.

We present a study of a Hanbury Brown–Twiss interferometer realized with anyons. Such a device can directly probe entanglement and fractional statistics of initially uncorrelated particles. We calculate Hanbury Brown–Twiss cross correlations of Abelian Laughlin anyons. The correlations we calculate exhibit partial bunching similar to bosons, indicating a substantial statistical transmutation from the underlying electronic degrees of freedom. We also find qualitative differences between the anyonic signal and the corresponding bosonic or fermionic signals, indicating that anyons cannot be simply thought of as intermediate between bosons and fermions.

We present a generating functional which describes the equilibrium thermodynamic response of a relativistic system to external sources. A variational principle gives rise to constraints on the response parameters of relativistic hydrodynamics without making use of an entropy current. Our method reproduces and extends results available in the literature. It also provides a technique for efficiently computing $n$-point zero-frequency correlation functions within the hydrodynamic derivative expansion without the need to explicitly solve the equations of hydrodynamics.

Using in situ imaging, we report surface fold formation and fluidlike flow instabilities in sliding of annealed copper. We demonstrate using simulations that folding is principally driven by grain-induced plastic instability. The phenomenon shows remarkable similarities with Kelvin-Helmholtz-type flow instabilities in fluids. While such instabilities have been conjectured to exist in sliding interfaces at the nanoscale, we find vortices and folding in metals at the mesoscale. The occurrence of folds impacts many applications, including surface generation processes and tribology.

The unrelated discoveries of quasicrystals and topological insulators have in turn challenged prevailing paradigms in condensed-matter physics. We find a surprising connection between quasicrystals and topological phases of matter: (i) quasicrystals exhibit nontrivial topological properties and (ii) these properties are attributed to dimensions higher than that of the quasicrystal. Specifically, we show, both theoretically and experimentally, that one-dimensional quasicrystals are assigned two-dimensional Chern numbers and, respectively, exhibit topologically protected boundary states equivalent to the edge states of a two-dimensional quantum Hall system. We harness the topological nature of these states to adiabatically pump light across the quasicrystal. We generalize our results to higher-dimensional systems and other topological indices. Hence, quasicrystals offer a new platform for the study of topological phases while their topology may better explain their surface properties.

Flowing blood displays a phenomenon called margination, in which leukocytes and platelets are preferentially found near blood vessel walls, while erythrocytes are depleted from these regions. Here margination is investigated using direct hydrodynamic simulations of a binary suspension of stiff ($s$) and floppy ($f$) capsules, as well as a stochastic model that incorporates the key particle transport mechanisms in suspensions—wall-induced hydrodynamic migration and shear-induced pair collisions. The stochastic model allows the relative importance of these two mechanisms to be directly evaluated and thereby indicates that margination, at least in the dilute case, is largely due to the differential dynamics of homogeneous (e.g. $s\mathrm{\text{−}}s$) and heterogeneous ($s\mathrm{\text{−}}f$) collisions.

We observe a giant spin-orbit splitting in the bulk and surface states of the noncentrosymmetric semiconductor BiTeI. We show that the Fermi level can be placed in the valence or in the conduction band by controlling the surface termination. In both cases, it intersects spin-polarized bands, in the corresponding surface depletion and accumulation layers. The momentum splitting of these bands is not affected by adsorbate-induced changes in the surface potential. These findings demonstrate that two properties crucial for enabling semiconductor-based spin electronics—a large, robust spin splitting and ambipolar conduction—are present in this material.

It has been predicted theoretically and demonstrated experimentally that a planar slab supporting surface plasmons or surface phonon polaritons can behave as a super lens. However, the resolution is limited by the losses of the slab. In this Letter, we point out that the resolution limit imposed by losses can be overcome by using time-dependent illumination.

A minimal model of a quantum refrigerator, i.e., a periodically phase-flipped two-level system permanently coupled to a finite-capacity bath (cold bath) and an infinite heat dump (hot bath), is introduced and used to investigate the cooling of the cold bath towards absolute zero ($T=0$). Remarkably, the temperature scaling of the cold-bath cooling rate reveals that it does not vanish as $T\to 0$ for certain realistic quantized baths, e.g., phonons in strongly disordered media (fractons) or quantized spin waves in ferromagnets (magnons). This result challenges Nernst’s third-law formulation known as the unattainability principle.

In this Letter, we report the first experimental realization and investigation of a spin-orbit coupled Fermi gas. Both spin dephasing in spin dynamics and momentum distribution asymmetry of the equilibrium state are observed as hallmarks of spin-orbit coupling in a Fermi gas. The single particle dispersion is mapped out by using momentum-resolved radio-frequency spectroscopy. From momentum distribution and momentum-resolved radio-frequency spectroscopy, we observe the change of fermion population in different helicity branches consistent with a finite temperature calculation, which indicates that a Lifshitz transition of the Fermi surface topology change can be found by further cooling the system.

The coupling of the spin of electrons to their motional state lies at the heart of recently discovered topological phases of matter. Here we create and detect spin-orbit coupling in an atomic Fermi gas, a highly controllable form of quantum degenerate matter. We directly reveal the spin-orbit gap via spin-injection spectroscopy, which characterizes the energy-momentum dispersion and spin composition of the quantum states. For energies within the spin-orbit gap, the system acts as a spin diode. We also create a spin-orbit coupled lattice and probe its spinful band structure, which features additional spin gaps and a fully gapped spectrum. In the presence of $s$-wave interactions, such systems should display induced $p$-wave pairing, topological superfluidity, and Majorana edge states.

When are athermal soft-sphere packings jammed? Any experimentally relevant definition must, at the very least, require a jammed packing to resist shear. We demonstrate that widely used (numerical) protocols, in which particles are compressed together, can and do produce packings that are unstable to shear—and that the probability of generating such packings reaches one near jamming. We introduce a new protocol which, by allowing the system to explore different box shapes as it equilibrates, generates truly jammed packings with strictly positive shear moduli $G$. For these packings, the scaling of the average of $G$ is consistent with earlier results, while the probability distribution $P(G)$ exhibits novel and rich scalings.

We present an analysis of finite-size effects in jammed packings of $N$ soft, frictionless spheres at zero temperature. There is a $\frac{1}{N}$ correction to the discrete jump in the contact number at the transition so that jammed packings exist only above isostaticity. As a result, the canonical power-law scalings of the contact number and elastic moduli break down at low pressure. These quantities exhibit scaling collapse with a nontrivial scaling function, demonstrating that the jamming transition can be considered a phase transition. Scaling is achieved as a function of $N$ in both two and three dimensions, indicating an upper critical dimension of 2.

We propose nonlinear resonant laser manipulation, a technique that drastically enhances the number of degrees of freedom when manipulating nano-objects. Considering the high laser intensity required to trap single molecules, we calculate the radiation force exerted on a molecule in a focused laser beam by solving the density matrix equations using the nonperturbative method. The results coherently elucidate certain recently reported puzzling phenomena that contradict the conventional understanding of laser trapping. Further, we demonstrate unconventional forms of laser manipulations using “stimulated recoil force” and “subwavelength laser manipulation.”

Pulsar timing arrays are a prime tool to study unexplored astrophysical regimes with gravitational waves. Here, we show that the detection of gravitational radiation from individually resolvable supermassive black hole binary systems can yield direct information about the masses and spins of the black holes, provided that the gravitational-wave-induced timing fluctuations both at the pulsar and at Earth are detected. This in turn provides a map of the nonlinear dynamics of the gravitational field and a new avenue to tackle open problems in astrophysics connected to the formation and evolution of supermassive black holes. We discuss the potential, the challenges, and the limitations of these observations.