Visual design intuition: predicting dynamic properties of beams from raw cross-section images.

In this work we aim to mimic the human ability to acquire the intuition to estimate the performance of a design from visual inspection and experience alone. We study the ability of convolutional neural networks to predict static and dynamic properties of cantilever beams directly from their raw cross-section images. Using pixels as the only input, the resulting models learn to predict beam properties such as volume maximum deflection and eigenfrequencies with 4.

Autonomous drone hunter operating by deep learning and all-onboard computations in GPS-denied environments.

This paper proposes a UAV platform that autonomously detects, hunts, and takes down other small UAVs in GPS-denied environments. The platform detects, tracks, and follows another drone within its sensor range using a pre-trained machine learning model. We collect and generate a 58,647-image dataset and use it to train a Tiny YOLO detection algorithm.

Phenomenological evidence for the phonon Hall effect.

In the electrical Hall effect, a magnetic field, applied perpendicular to an electrical current, induces through the Lorentz force a voltage perpendicular to the field and the current. It is generally assumed that an analogous effect cannot exist in the phonon thermal conductivity, as there is no charge transport associated with phonon propagation. In this Letter, we argue that such a magnetotransverse thermal effect should exist and experimentally demonstrate this "phonon Hall effect" in Tb3Ga5O12.

Magnetoelectric anisotropy in diffusive transport.

In this Letter we prove the existence of a new general diffusive transport phenomenon in crossed electric and magnetic fields: magnetoelectric anisotropy. For the specific case of diffusive electrical transport, we present a relativistic model to quantify this effect and present experimental evidence for its existence.

Fine structure of effective mass acceptors in gallium nitride.

Magnetoluminescence of the exciton bound to a neutral acceptor was measured to investigate the electronic structure of a shallow acceptor center in GaN. The application of magnetic fields along different directions with respect to the crystal c axis allowed us to determine the symmetry of the ground (Gamma(9)) and the first excited state (Gamma(7)) of the acceptor. The observed Zeeman splitting pattern has axial symmetry but can be explained well only by assuming a significant reduction of the spin-orbit interaction for this acceptor state.

Ring-shaped vortex domain in type-II superconductors.

We present results of experiments in superconducting niobium and numerical simulations showing the creation of a metastable ring-shaped vortex domain by heating. Such vortex rings, if pinned by structural defects, can exist forever.

Current-driven resonances in magnetic multilayers.

We describe complex variations in resistance of a Co/Cu multilayer, generated by injection of an adjustable dc current density ( approximately 10(9) A/cm(2)) via a point contact. We attribute these variations to coupling of current-induced spin waves to lattice vibrations, leading especially to current-driven resonant excitations of phonons. We propose a simple model to explain the observed structured behavior of the variations as a function of the applied current and magnetic field.

Slow oscillations of magnetoresistance in quasi-two-dimensional metals.

Slow oscillations of the interlayer magnetoresistance observed in the layered organic metal beta-(BEDT-TTF)(2)IBr(2) are shown to originate from the slight warping of its Fermi surface rather than from independent small cyclotron orbits. Unlike the usual Shubnikov-de Haas effect, these oscillations are not affected by the temperature smearing of the Fermi distribution and can therefore become dominant at high enough temperatures. We suggest that the slow oscillations are a general feature of clean quasi-two-dimensional metals and discuss possible applications of the phenomenon.

Observation of magnetoelectric directional anisotropy.

We report the first observation of a new optical phenomenon, magnetoelectric directional anisotropy (MEA). MEA is a polarization-independent anisotropy which occurs in crossed electric field E and magnetic field B perpendicular to the wave vector k of the light. It is described by a contribution to the refractive index of the form (delta)n=(gamma)k x E x B.

Electrical magnetochiral anisotropy.

Electrical conductors can be chiral, i.e., can exist in two forms where one is the other's mirror image.

Magnetotransverse scattering of surface plasmon polaritons.

We show experimentally that the in-plane scattering of surface plasmon polaritons (SPP) is influenced by a perpendicular magnetic field. The average SPP flux is deflected into the direction perpendicular to both its initial propagation direction and the magnetic field direction. From a phenomenological point of view, this is an analogy to the Hall effect for electrons and a 2D equivalent of the photonic Hall effect.

History effects and phase diagram near the lower critical point in YBa2Cu3O7 single crystals.

Using a sensitive torque magnetometer we have studied magnetization curves for untwinned overdoped YBa2Cu3O7 single crystals in fields of up to 28 T. We demonstrate the existence of history effects below the lower critical point and provide a full demarcation of the Bragg-glass phase. A pronounced symmetry is observed in the behavior of the phase lines, irreversible magnetization, and value of the magnetization jump near both critical points.

Generation and detection of phase-coherent current-driven magnons in magnetic multilayers.

The magnetic state of a ferromagnet can affect the electrical transport properties of the material; for example, the relative orientation of the magnetic moments in magnetic multilayers underlies the phenomenon of giant magnetoresistance. The inverse effect--in which a large electrical current density can perturb the magnetic state of a multilayer--has been predicted and observed experimentally with point contacts and lithographically patterned samples. Some of these observations were taken as indirect evidence for current-induced excitation of spin waves, or 'magnons'.

Principles and performance of an electron spin echo spectrometer using far infrared lasers as excitation sources.

We have built an electron spin echo spectrometer operating at 604 GHz, extending the frequency limit of existing spectrometers by more than a factor of 4. In order to handle this high frequency we have used optical techniques, i.e.