Large, Tunable Magnetoresistance in Nonmagnetic III–V Nanowires

Abstract

Magnetoresistance, the modulation of resistance by magnetic fields, has been adopted and continues to evolve in many device applications including hard-disk, memory, and sensors. Magnetoresistance in nonmagnetic semiconductors has recently raised much attention and shows great potential due to its large magnitude that is comparable or even larger than magnetic materials. However, most of the previous work focus on two terminal devices with large dimensions, typically of micrometer scales, which severely limit their performance potential and more importantly, scalability in commercial applications. Here, we investigate magnetoresistance in the impact ionization region in InGaAs nanowires with 20 nm diameter and 40 nm gate length. The deeply scaled dimensions of these nanowires enable high sensibility with less power consumption. Moreover, in these three terminal devices, the magnitude of magnetoresistance can be tuned by the transverse electric field controlled by gate voltage. Large magnetoresistance between 100% at room temperature and 2000% at 4.3 K can be achieved at 2.5 T. These nanoscale devices with large magnetoresistance offer excellent opportunity for future high-density large-scale magneto-electric devices using top-down fabrication approaches, which are compatible with commercial silicon platform.

Control of Positive and Negative Magnetoresistance in Iron Oxide–Iron Nanocomposite Thin Films for Tunable Magnetoelectric Nanodevices

“…Also, a transfer to solid electrolytes with similar redox behavior may be possible. 19 The large range of positive and negative MR values set by the thickness and a low voltage (∼1 V) at room temperature goes beyond state-of-theart voltage-tunable MR devices, which are restricted to positive or negative MR, 11,16,17 high applied voltage, 15,17 or lowtemperature operation. 12,15,61 In summary, we investigated the MR of iron oxide−iron nanocomposite films for nominal sputtered iron thicknesses d Fe,nom from 5 to 50 nm.…”

“…The understanding and control over magnetoresistance (MR) in nanostructured materials is crucial for the development of modern magnetic sensors, , high-density information storage, spintronics, , biochips, magnetoelectronic logic devices or microwave nanoelectronics . Intense research efforts have been focussed on tailoring MR by optimizing the material composition and nanostructure, and, ideally, finding systems in which MR is tunable by an external control parameter, e.g ., by electric fields or optical modulation. , In semiconductor nanowires − and spin-valve devices, as well as atomically thin Weyl semimetals, large changes of MR by electric field effects have been demonstrated. However, in these cases, the tunable MR becomes significant only at low temperatures (<5 K) or the synthesis routes are complex.…”

Transition from positive to negative magnetoresistance induced by a constriction in semiconductor nanowire

“…Recent studies on nonmagnetic III-V nanowires suggest such possibility for future high-density magneto-electric devices, compatible with commercial silicon technology. 29 The available experimental reports show that the change of MR sign can be related to the applied gate voltage in a number of different materials, including organic semiconductors 18 and carbon nanotubes 22 . Electric control of MR, both its sign and magnitude, was also reported in the case of InP nanowires.…”

Tunable electron heating induced giant magnetoresistance in the high mobility GaAs/AlGaAs 2D electron system

“…Semiconductor GMR is particularly interesting for applications because of the expected ease of integration of associated devices with typical semiconductor electronics3. As a consequence, the study of potential new mechanisms for realizing GMR in semiconductors has been a useful line of basic research78910. Semiconductor GMR in disordered 2D electronic systems has also been a topic of interest from the fundamental physics perspective111213141516171819202122232425262728, providing insight into weak localization1117, weak anti-localization1117, electron-electron interaction-induced magnetoresistance1114151618192223, metal-insulator transitions induced by a magnetic field29, and GMR in the quantum Hall regime3031.…”

“…While previous studies have examined electric field control of magnetoresistance7910, we show that a supplementary dc-current-bias and associated carrier heating in an ac- and dc- current biased high mobility 2DES provides for a current dependent “non-ohmic” decrease in the conductivity with increasing dc current bias in the absence of a magnetic field, and this effect leads to a dc-current tunable GMR in the presence of 100’s-of-millitesla-type magnetic fields. Thus, the effect identifies a simple new method for setting the magnitude of the GMR effect as desired, in a semiconductor system.…”