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Antiferromagnets are a class of magnetically ordered material with zero net magnetization. A swathe of recent experimental studies have shown that electrical control of antiferromagnetic order is possible by two distinct mechanisms: field-like and damping-like torques. This could be revolutionary for the next generation of computing technologies, as the properties of antiferromagnets are advantageous for high speed, high density memory applications. Here, we review the electrical control of antiferromagnets via field-like and damping-like torques as well as distinguishing from pervasive non-magnetic effects that have raised questions about the origins of electrically measured switching signals.

A new type of ion source is being developed for proton beam writing and other focused ion beam applications. The potential of this source as well as achieved performance of the nano aperture ion source will be evaluated. Based on the ideal source parameters, critical geometrical parameters constraining chromatic aberrations and a possible pathway to achieve this performance will be presented. Finally, an electronic control system to minimize chromatic and spherical aberrations to an acceptable level will be demonstrated.

Refined electrical control of the flow of red blood cells facilitates tests of plasma components.

We achieved the electrical control of a magnetic state by using an external magnetic field via electric field-induced resistance (EIR) change phenomena. We prepared a La0.7Sr0.3MnO3 (LSMO) film which showed EIR changes. Before the EIR treatment, the sample barely showed negative magnetoresistance (MR). After the EIR treatment, the value of negative MR became six times larger than that before the EIR treatment. The magnetization curves also changed from paramagnetism to superparamagnetism. These behaviors revealed that the EIR treatment changed not only the resistance state but also the magnetic state in LMSO film.

The response of a single InGaAs quantum dot, embedded in a miniaturized charge-tunable device, to an applied GHz bandwidth electrical pulse is investigated via its optical response. Quantum dot response times of 1.0 \pm 0.1 ns are characterized via several different measurement techniques, demonstrating GHz bandwidth electrical control. Furthermore a novel optical detection technique based on resonant electron-hole pair generation in the hybridization region is used to map fully the voltage pulse experienced by the quantum dot, showing in this case a simple exponential rise.

We have studied single-electron turnstile operation in common-gated one-dimensional arrays of four tunnel junctions (three dots) having inhomogeneous junction capacitances. Analytical calculations show that the source-drain voltage range with a current plateau due to single-electron turnstile operation is increased when the outer two tunnel capacitances are adjusted to be smaller than the inner ones. In fact, we have demonstrated in phosphorous-doped silicon-on-insulator field-effect transistors (FETs) that back-gate voltage works to assist the turnstile operation, which is primarily ascribed to electrical control of junction capacitance dispersion, i.e., reduction in outer junction capacitances. As a result, postfabrication control of capacitance dispersion in multijunction FETs can be achieved, resulting in successful turnstile operation.

This study demonstrates the electrical control of the surface wettability of liquid crystal and polymer composite film. The application of external voltages significantly affects the surface wettability of the film. This study uses atomic force microscopy to quantitatively characterize the fundamental mechanism responsible for the structurally driven changes in surface properties at various applied voltages. The surface wettability transitions of the film are electrically driven, as shown by reorganized liquid crystal molecules. Measurements of the voltage-dependent surface wettability of the composite film suggest approaches to supporting control applications of future electro-optical nanotechnology devices.

We calculate that the electron states of strained self-assembled Ge/Si quantum dots provide a convenient two-state system for electrical control. An electronic state localized at the apex of the quantum dot is nearly degenerate with a state localized at the base of the quantum dot. Small electric fields shift the electronic ground state from apex-localized to base-localized, which permits sensitive tuning of the electronic, optical and magnetic properties of the dot. As one example, we describe how spin-spin coupling between two Ge/Si dots can be controlled very sensitively by shifting the individual dot's electronic ground state between apex and base.

We demonstrate electrical control of the optical sensitivity function in multiple quantum wells (MQWs) for nanoacoustic wave detection. This is realized by bias controlling the quantized level and the quasi-Fermi level of carrier-populated InGaN/GaN MQWs. Experimentally, a strongly bias-dependent optical sensitivity was observed when the optical probe transition was near the quasi-Fermi level, which agrees well with the theoretical prediction.

We propose a new integrated interferometric reflector (IIR) with electrical control. The IIR is suitable for incorporation in integrated optical devices as a laser reflector.

Single‐crystal Sr0.75Ba0.25Nb2O6 when used in conjunction with an externally applied electric field is shown to be a sensitive volume holographic medium capable of high‐resolution information storage. Optically induced refractive index changes of 5 × 10−4 have been observed with laser exposure of 14 J/cm2. A simple relation between the applied electric field and optical exposure is determined which allows electrical control of optically induced refractive index change. In addition to control of the optically induced effect it is found that the applied electric field can also be used to control the diffraction efficiency of the holographic reconstruction process.