Conductivity control in SmxMn1–xS by magnetic field and current

Spacecraft electronics and onboard computer microchips are made of semiconductors. Radiation increases in near-Earth orbit, especially during solar flares, where the flux of high-energy particles and gamma radiation increases. This leads to defects in semiconductor transistors and failure of electronic devices. Therefore, replacing field-effect transistors with spintronics, which utilizes the spin degree of freedom of electrons, is becoming a pressing issue. Transport characteristics can be controlled by a magnetic field using samarium-substituted manganese sulfides. The conductivity of a sample was studied at low current in a magnetic field applied at an angle to the current, varying from 0° to 360°. Without a magnetic field, the conductivity remains constant. When a magnetic field is applied and the sample rotates, a change in conductivity is observed. In a magnetic field, conductivity decreases and reaches a minimum within a certain angular range. Upon heating, conductivity decreases in a magnetic field and reaches one order of magnitude near the magnetic phase transition. The current-voltage characteristics of SmxMn1–xS with a concentration of x = 0.1 were measured without a magnetic field of H = 0 kOe and in a magnetic field of H = 12 kOe, directed along the current and perpendicular to the current. The dependence of current on voltage is nonlinear and is associated with electrically inhomogeneous states in the sample. From the current-voltage characteristics, the dependence of the change in conductivity in a magnetic field on the current (voltage) and temperature was found. The maximum decrease in conductivity in a magnetic field was found at 200 K. Above room temperature, conductivity decreases by several percent due to the Hall contribution. Heating and increasing current lead to a decrease in magnetoconductivity. A comparison of the two methods for measuring conductivity in a magnetic field indicates that the regulation of conductivity by a magnetic field depends on the current value at which the conductivity is measured.