Electric breakdown in ultrathin MgO tunnel barrier junctions for spin-transfer torque switching

Schäfers, Markus; Drewello, Volker; Reiss, Günter; Thomas, Andy; Thiel, Karsten; Eilers, Gerrit; Münzenberg, Markus; Schuhmann, Henning; Seibt, M.

doi:10.1063/1.3272268

Cited by 30 publications

(15 citation statements)

References 19 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…[24,25] Recently, it was proposed that graphene could serve as a low-resistance tunnel barrier for vertical SV consisting of ferromagnet/graphene/ferromagnet junctions due to its features of single atomic layer thickness, zero-bandgap, and large area growth without pinholes. [24,25] Recently, it was proposed that graphene could serve as a low-resistance tunnel barrier for vertical SV consisting of ferromagnet/graphene/ferromagnet junctions due to its features of single atomic layer thickness, zero-bandgap, and large area growth without pinholes.…”

mentioning

confidence: 99%

Graphene/Half‐Metallic Heusler Alloy: A Novel Heterostructure toward High‐Performance Graphene Spintronic Devices

Larionov

Попов

et al. 2019

Advanced Materials

View full text Add to dashboard Cite

For years graphene has been considered as the most potential material which paves the way to advanced spintronic devices [1][2][3][4][5][6] due to its extraordinary electrical and physical properties. [7][8][9][10] The long spin diffusion length in graphene originated from the weak spin-orbit interaction and high electron mobility have stimulated numerous studies on developing graphene-based lateral spin valve (SV) in the past decade. [11][12][13][14][15][16] Apart from the application to lateral SV dealing with in-plane spin transport in a graphene channel, another potential application that is the implementation of graphene as a spacer material in vertical SV has recently become a subject of intense interest. [17][18][19][20][21][22] In development of vertical SV, the achievement of both the low resistance-area (RA) product and large magnetoresistance (MR) ratio is required for the realization of read heads for ultrahigh-density hard disk drives, [23] and magnetic random access memory [5,6] with high-speed operation and low power consumption. However, the current technology Graphene-based vertical spin valves (SVs) are expected to offer a large magnetoresistance effect without impairing the electrical conductivity, which can pave the way for the next generation of high-speed and low-power-consumption storage and memory technologies. However, the graphene-based vertical SV has failed to prove its competence due to the lack of a graphene/ferromagnet heterostructure, which can provide highly efficient spin transport. Herein, the synthesis and spin-dependent electronic properties of a novel heterostructure consisting of single-layer graphene (SLG) and a half-metallic Co 2 Fe(Ge 0.5 Ga 0.5 ) (CFGG) Heusler alloy ferromagnet are reported. The growth of high-quality SLG with complete coverage by ultrahigh-vacuum chemical vapor deposition on a magnetron-sputtered single-crystalline CFGG thin film is demonstrated. The quasi-free-standing nature of SLG and robust magnetism of CFGG at the SLG/ CFGG interface are revealed through depth-resolved X-ray magnetic circular dichroism spectroscopy. Density functional theory (DFT) calculation results indicate that the inherent electronic properties of SLG and CFGG such as the linear Dirac band and half-metallic band structure are preserved in the vicinity of the interface. These exciting findings suggest that the SLG/CFGG heterostructure possesses distinctive advantages over other reported graphene/ferromagnet heterostructures, for realizing effective transport of highly spin-polarized electrons in graphene-based vertical SV and other advanced spintronic devices.

show abstract

mentioning

confidence: 99%

Graphene/Half‐Metallic Heusler Alloy: A Novel Heterostructure toward High‐Performance Graphene Spintronic Devices

Larionov

Попов

et al. 2019

Advanced Materials

View full text Add to dashboard Cite

show abstract

“…We swept the voltage from zero to −600 to 600 mV and back to zero. Voltages of more than 600 mV led to a dielectric breakdown of the junctions (Thomas et al, 2008 ; Schaefers et al, 2009 ). All measurements are done with the bottom electrode as the reference potential.…”

Section: Resultsmentioning

confidence: 99%

“…These values are close to the dielectric breakdown voltage of the devices. Transmission electron microscopy images of MgO junctions before and after the dielectric breakdown are presented in our previous work (Thomas et al, 2008 ; Schaefers et al, 2009 ). Consequently, the investigations utilizing sequences of voltage pulses were limited to a maximum voltage of 500 mV.…”

Section: Methodsmentioning

confidence: 98%

“…The alignment of the softer magnetic layer can be switched by current pulses because the spin of the tunneling electrons is flipped and leads to a torque, eventually switching the magnetization (Huai et al, 2004 ). Magnesia based MTJs exhibit on/off ratios of 2, switching voltages of approximately 500 mV and switching times in the order of ns (Kishi et al, 2008 ; Schaefers et al, 2009 ).…”

Section: Alternate Mechanisms For Memristive/resistive Switchingmentioning

confidence: 99%

See 1 more Smart Citation

Tunnel junction based memristors as artificial synapses

et al. 2015

View full text Add to dashboard Cite

We prepared magnesia, tantalum oxide, and barium titanate based tunnel junction structures and investigated their memristive properties. The low amplitudes of the resistance change in these types of junctions are the major obstacle for their use. Here, we increased the amplitude of the resistance change from 10% up to 100%. Utilizing the memristive properties, we looked into the use of the junction structures as artificial synapses. We observed analogs of long-term potentiation, long-term depression and spike-time dependent plasticity in these simple two terminal devices. Finally, we suggest a possible pathway of these devices toward their integration in neuromorphic systems for storing analog synaptic weights and supporting the implementation of biologically plausible learning mechanisms.

show abstract

“…Because the TMR effect measured in the fabricated device reached 100%, a higher sensitivity is also expected [10]. In case of TMR device, the maximum voltage applied to the tunneling barrier cannot exceed 1.5 V, because of a possibility of the electrical breakdown [11]. The input power in this case was, therefore, limited to in = -10 dBm, which resulted in TMR = 1.1 W. At resonance condition (test frequency 1.6 GHz and external magnetic field H = 600 Oe) the output power reached 45 W and sensitivity was calculated to 86 V/W.…”

Section: Tmrmentioning

confidence: 95%

Microwave detection based on magnetoresistance effect in spintronic devices

Skowroński

Ziętek

Cecot

et al. 2016

2016 21st International Conference on Microwave, Radar and Wireless Communications (MIKON)

View full text Add to dashboard Cite

We demonstrate a radio-frequency electromagnetic signal detection in spintronic devices utilizing various magnetoresistance effects. Different device layout is proposed such as tunneling magnetoresistance nano-pillar or giant magnetoresistance stripe, which enable DC voltage generation when a device is supplied with radio-frequency current. Depending on the detection method, sensitivity of up to 80 V/W was achieved in a frequency range between 1 -10 GHz, depending on the magnetic field.

show abstract

Electric breakdown in ultrathin MgO tunnel barrier junctions for spin-transfer torque switching

Cited by 30 publications

References 19 publications

Graphene/Half‐Metallic Heusler Alloy: A Novel Heterostructure toward High‐Performance Graphene Spintronic Devices

Graphene/Half‐Metallic Heusler Alloy: A Novel Heterostructure toward High‐Performance Graphene Spintronic Devices

Tunnel junction based memristors as artificial synapses

Microwave detection based on magnetoresistance effect in spintronic devices

Contact Info

Product

Resources

About