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In this study, we analyze the evolution of current-voltage characteristics of a quasi-one-dimensional TaS3 conductor under uniaxial tension in the temperature range of 150–40 K. At all temperatures, elongation is found to lead to formation of an “ultracoherent” charge density wave (CDW) the main feature of which is a sharp increase in conductivity under an electric field that is higher than the threshold: above 100 K, the transition in the dependence on e occurs almost abruptly while, below 90 K, elongation leads to an intermediate region in which the threshold field increases sharply and is poorly defined due to weak nonlinear conductivity. The result proves the occurrence of a spatially non-uniform state of the CDW below 90 K.

Quasi-one-dimensional conductors with charge-density wave (CDW), which are used to excite and detect mechanical oscillations, are considered. The effect of elongation e of whiskers of a quasi-one-dimensional conductor (orthorhombic TaS3) on the excited resonance oscillation modes is studied by means of heterodyning. Dependences of the oscillation frequency on e allow one to distinguish bending and torsional modes. The magnitude of the detected signal increases sharply at ec ≈ 0.6% in the region of CDW transition into the ultracoherent (UC) state. This effect is attributed to an anomalously strong piezoresistive response; in the UC state (e > ec), the signal virtually vanishes.

Heterodyne mixing with frequency modulation is employed for detection of torsional resonances of whiskers in rhombic TaS3 (typical quasi-1D conductor) with charge-density wave (CDW). The dependences of both torque and the feedback signal of torsion on the internal properties of CDW are distinctive features of the proposed method. Sample placement in the vicinity of the electrode that serves as gate is unnecessary. Electromechanical and elastic properties of the CDW systems can be studied with the aid of the proposed method, at least, in the megahertz frequency range.

It has recently been proved that, in alloys, e.g., based on the Ti–Ni system, a shape memory effect (SME) is preserved down to the nanoscale sizes of an active alloy layer and demonstrated ultrasmall-sized and fully functional microand nanomechanical devices: actuators and nanotweezers that are fabricated via standard microelectronic technologies relying on composite materials with the SME. In the nearest future, such achievements will enable the creation of the next-generation microand nanomechanical devices whose sizes are quite comparable with those inherent to, e.g., carbon nanotubes, graphene sheets, viruses, etc. Mathematical simulation methods are used to study how the shape-memory micromechanical devices can be activated by means of resistive pulse heating. A decrease in the overall sizes of heating elements (from 1 mm to 10 μm) is demonstrated to be accompanied by the fact that the speed of operation increases sharply from 102 to 105 s–1 and, simultaneously, the energy consumption diminishes from 10–3 to 10–8 J per operation. The preliminary results of experiments whereby the control of the composite nanotweezer exhibiting the SME is perfected with the help of the automatic pulsed heating technology, as well as the prospects for creating high-speed and high-performance microrobotic systems incorporating newly developed components, are discussed.