Magnetic field effects on the nonohmic impurity conduction of uncompensated crystalline silicon

Anomalous Conductance near Percolative Metal–Insulator Transition in Monolayer MoS2 at Low Voltage Regime

“…In monolayer MoS 2 , we observed this behavior in the sample with a relatively high four-probe field-effect mobility of μ FE = (1/C ox )(dσ/dV G ) ≈ 600 cm 2 V −1 s −1 calculated at V ds = 0.1 V and T = 20 K, where C ox is the geometrical oxide capacitance of 300 nm thick SiO 2 (Supporting Information S2) because it requires the large site spacing to have numerous dead ends or returns as this phenomenon has usually been observed in the low compensated semiconductor systems. 18,19 μ FE decreases rapidly with the increase of V ds , as shown in Figure 3f as it is calculated with the conductivity in the regime of the metallic phase.…”

“…In particular, in the low-field regime, the decrease of the conductivity as E increases in the insulating phase (e.g., σ for T ≥ 40 K at V G = 30 V in Figure 2b) contrasts the usual insulating behavior and strongly supports this suggestion. This behavior has been experimentally observed in low compensated semiconductors 18,19 and interpreted as a result of "dead ends", that is, the sites distant from neighboring sites, so that the hopping probabilities to them are negligible in the percolation picture 20 or "returns", that is, the twisted paths containing the segments where electrons travel along the field. 9 In a two-probe measurement, this phenomenon is not seen due to the high contact resistance (Supporting Information Figure S1).…”

Unravelling the mechanism of large room-temperature magnetoresistance in silicon

“…(Some figures in this article are in colour only in the electronic version) Silicon holds exceptional promise for magnetoelectronics, by virtue of its long spin coherence [1,2] and compatibility with the current CMOS technology. Within the past decades, the influence of a magnetic field on the carrier transport in silicon devices has been investigated frequently [3][4][5][6][7][8]. As a possible implicit contribution for future silicon based spintronics devices, and in line with a reported novel magnetoresistance in semi-insulating-GaAs Schottky diodes [9], we have recently shown a robust low temperature positive magnetoresistance over 10 000% of magnitude in lateral boron-doped Si/SiO 2 /Al devices [10,11].…”

Large magnetoresistance in Si:B-SiO2-Al structures

“…[4][5][6][7] In line with a reported novel magnetoresistance effect in GaAs, 8 we show at low temperatures in boron-doped Si-SiO 2 -Al structures a robust symmetric positive resistance change of eight orders of magnitude at relatively small magnetic fields of 500 mT. In contrast to other reports on silicon, the magnitude of this resistance change is significantly higher at much smaller magnetic fields, and, moreover, it can be efficiently tuned by the control over the silicon-oxide layer separating the silicon from the nonmagnetic electrodes.…”