Epitaxial InGaAs/InAlAs/AlAs Structures for Heterobarrier Varactors with Low Leakage Current

The quality of heteroboundaries and optimal conditions for epitaxial growth are critical parameters for obtaining low leakage currents of heterobarrier varactors in the InGaAs/InAlAs/AlAs material system. Grown by molecular-beam epitaxy, three-barrier heterobarrier varactor structures adjacent to InAlAs/AlAs/InAlAs barrier layers by additional mismatched InGaAs layers subjected to compressive stress show, under optimal epitaxy conditions, extremely low levels of leakage current density (not more than 0.06 A/cm² at a voltage of 5 V and 85°C) with relatively thin AlAs inserts (with a thickness of 2 nm).     

Stationary charged surface configuration of a conducting liquid in the long-wavelength limit

A particular solution to the problem of an equilibrium configuration of the surface of a conducting liquid in an external electric field is constructed based on an analysis of the balance of gravitational and electrostatic forces. The solution corresponds to a cone-shaped crater with a cone angle of 136.26°. The possibility of generalizing the obtained exact solution to the case of a dielectric liquid is considered.     

Role of the polyclinic examination room in detecting breast cancer and precancer

The authors review their 5-year experience with the work of the women's diagnostic department for recognition of cancer and precancer of the mammary gland. The efficacy of the activities of this diagnostic department is believed to be determined by two main factors: 1) proper organization of its activity and 2) its close contacts with an oncologist of the polyclinic.