Multi-terminal spin valve in a strong Rashba channel exhibiting three resistance states

Abstract

In a strong spin-orbit interaction system, the existence of three resistance states were observed when two ferromagnetic (FM) contacts were used as current terminals while a separate normal metal contact pair was used as voltage terminals. This result is strikingly different from ordinary spin valve or magnetic tunnel junction devices, which have only two resistance states corresponding to parallel (RP) and antiparallel (RAP) alignments of the FM contacts. Our experimental results on a quantum well layer with a strong Rashba effect clearly exhibit unequal antiparallel states, i.e., RAP(1) > RP > RAP(2), up to room temperature. The three-states are observed without any degradation when the distance between the non-magnetic voltage probe and the ferromagnetic current probe was increased up to 1.6 mm.

Electrical detection of the inverse Edelstein effect on the surface of SmB6

“…We note that a diffusive spin current with the spin anti-parallel to the accumulated spin should flow in the direction opposite to the direction of the charge accumulation due to the zero net current along the x axis. Since the direction of the majority spin of Py is opposite to that of its magnetization and the majority spin of Py is mainly coupled to the SmB6 surface channel, the contact resistance between Py and spin-up channel of the SmB6 is larger (smaller) than that between Py and spindown channel of the SmB6 for M parallel to the +y (-y) direction [24,25].…”

“…2 The IEE signal also can be analysed quantitatively using the Onsager reciprocal relation. The Onsager reciprocal relation is the universal relation for any setup in the linear response regime, stating that the ratio of the measured voltage to a bias current does not change even when exchanging voltage and current terminals [25,26]. However, for time-reversal symmetry breaking field such as M, the sign of that field should be reversed to satisfy the reciprocity relation.…”

Rectification in Spin-Orbit Materials Using Low-Energy-Barrier Magnets

“…(1) has been observed on diverse spinorbit materials e.g. topological insulator (TI) [3][4][5][6], Kondo insulators [23], transition metals [7], semimetals [24], and semiconductors [8].…”

“…(1) from a highly resistive SML channel (e.g. TI [3][4][5][6], semiconductor [8], etc.) using a metallic FM, usually a thin tunnel barrier is inserted at the interface.…”

Unified Framework for Charge-Spin Interconversion in Spin-Orbit Materials

“…[4,5]) for beyond conventional computing, spin battery [6], flexible electronics [7], metallic rectifier [8], etc. Over the past decade, a large number of materials have been studied as possible elements of the spin-charge interconversion including topological insulators (TI) [9][10][11][12][13][14], semiconductors [15,16], transition metals [3,[17][18][19][20][21][22][23][24], semimetals [25], oxides [26][27][28][29], antiferromagnets [30], superconductor [31], etc. The sheer variety of materials that show such spin-charge interconversion is exciting, but it also poses a daunting challenge in terms of understanding the underlying physics and therefore designing a material system with the desired properties.…”