Room-Temperature Electron Spin Transport in a Highly Doped Si Channel

Suzuki, Toshio; Sasaki, T.; Oikawa, Tohru; Shiraishi, Masashi; Suzuki, Yoshishige; Noguchi, K.

doi:10.1143/apex.4.023003

Cited by 209 publications

(207 citation statements)

References 17 publications

Supporting

Mentioning

200

Contrasting

Order By: Relevance

“…However, the magnitude of the non-local signal in our study at room temperature is more than four-orders of magnitude higher than what has been measured in Si (~ 1 mΩ) 42 . Even compared with the highest spin signal obtained in graphene spin valves 34 , our result is order of magnitude comparable.…”

contrasting

confidence: 82%

Gate-tunable black phosphorus spin valve with nanosecond spin lifetimes

et al. 2017

View full text Add to dashboard Cite

Two-dimensional materials offer new opportunities for both fundamental science and technological applications, by exploiting the electron's spin 1 . While graphene is very promising for spin communication due to its extraordinary electron mobility, the lack of a band gap restricts its prospects for semiconducting spin devices such as spin diodes and bipolar spin transistors 2 . The recent emergence of 2D semiconductors could help overcome this basic challenge. In this letter we report the first important step towards making 2D semiconductor spin devices. We have fabricated a spin valve based on ultra-thin (~ 5 nm) semiconducting black phosphorus (bP), and established fundamental spin properties of this spin channel material which supports all electrical spin injection, transport, precession and detection up to room temperature (RT). Inserting a few layers of boron nitride between the ferromagnetic electrodes and bP alleviates the notorious conductivity mismatch problem and allows efficient electrical spin injection into an n-type bP. In the non-local spin valve geometry we measure Hanle spin precession and observe spin relaxation times as high as 4 ns, with spin relaxation lengths exceeding 6 µm. Our experimental results are in a very good agreement with first-principles calculations and demonstrate that Elliott-Yafet spin relaxation mechanism is dominant. We also demonstrate that spin transport in ultra-thin bP depends strongly on the charge carrier concentration, and can be manipulated by the electric field effect. 2 Electron spin is an important degree of freedom which can complement or even replace charge in information storage and logic devices 3 . For spin-based electronics, it is essential to have materials with long spin relaxation times at RT 1 . With respect to the material selection, semiconductors in particular offer new opportunities that are unfeasible in metal-based spintronics devices. These include doping by the electric field effect and gate controlled amplification/switching actions 4 . The boom of semiconductor spintronics started with the demonstration of the electrical spin injection into GaAs by R. Fiederling et al., also later by H.Ohno et al. 5,6 . I. Appelbaum and his colleagues further fostered this by adding silicon into the spintronics materials family 7 . More recently 2D materials such as graphene have captured the interest of engineers and scientists on the grounds of their high electronic mobility and the simultaneous ability to tune their charge carrier concentrations by the electric field effect 8 .Graphene has already been investigated very extensively in the spintronics community since the first unequivocal demonstration of RT spin injection by N. Tombros et al., 1,9 . While the first devices showed spin lifetimes of only 0.1 ns 9 , the new generation of graphene devices that have surfaces within the last year show remarkable spin lifetimes of ~ 10 ns, making graphene suitable for spin communication channels 10 .Conversely, the zero-band gap nature of graphene does not al...

show abstract

contrasting

confidence: 82%

Gate-tunable black phosphorus spin valve with nanosecond spin lifetimes

et al. 2017

View full text Add to dashboard Cite

show abstract

“…However, in spite of all the recent progress in the Ge field and in contrast to Si, spin transport in Ge using nonlocal four-terminal techniques has only been observed at low temperatures to date [30][31][32]. Spin transport has been reported through a Ni/Ge/AlGaAs [8,9] spin lifetime (non-local Hanle) (ns) [10] spin lifetime (ESR) (ns) [11][12][13] 10 n 0.3 10 300 300 n 0.3 1 8.5 300 p 0.27 -- Figure 3 Proposed spin field effect transistor (Spin FET) device, after Datta and Das [5]. Figure 4 The cornerstones of germanium spintronics, the generation, manipulation and detection of spin polarisation.…”

mentioning

confidence: 99%

Strained germanium for applications in spintronics

Morrison

Myronov

2016

Physica Status Solidi (a)

View full text Add to dashboard Cite

Germanium (Ge) is another group-IV semiconductor material, which recently started attracting tremendous attention in spintronics following success of silicon (Si). The crystal inversion symmetry of Si and Ge precludes the spin relaxation of conduction electrons by the Dyakonov-Perel mechanism, resulting in a long spin relaxation time. Since the proposal of the spin FET in 1990 by Datta and Das, semiconductor materials have been studied for their spin-orbit (S-O) interactions, particularly those that can be modified by an applied electric field, such as the Rashba S-O interaction, in order to create devices that utilise spin modulation and control to perform logic operations. Since then new proposals have appeared. Nowadays they include spin transistors with several different operating principles, spin-based diodes, spin-based field programmable gate arrays, dynamic spin-logic circuits, spin-only logic, spin communication and others. In this review, the focus will be made on presenting recent progress in Ge spintronics including the key advances made. The absence of Dresselhaus S-O coupling in Ge enables a longer spin diffusion length when compared to III-V semiconductor materials. Evidence of a strong Rashba S-O interaction in strained Ge quantum wells has begun to emerge. Also, the first experimental demonstration of room-temperature spin transport in Ge has recently been reported.

show abstract

“…The structure has been successfully used to measure spin transport through various metallic [6][7][8] and semiconducting [9,10] materials. LSVs consist of two ferromagnetic (FM) electrodes bridged by a nonmagnetic (NM) nanowire.…”

mentioning

confidence: 99%

Spin relaxation through Kondo scattering in Cu/Py lateral spin valves

et al. 2015

View full text Add to dashboard Cite

The temperature dependence of the spin diffusion length typically reflects the scattering mechanism responsible for spin relaxation. Within nonmagnetic metals it is reasonable to expect the Elliot-Yafet mechanism to play a role and thus the temperature dependence of the spin diffusion length might be inversely proportional to resistivity. In lateral spin valves, measurements have found that at low temperatures the spin diffusion length unexpectedly decreases. By measuring the transport properties of lateral Py/Cu/Py spin valves, fabricated from Cu with magnetic impurities of <1 ppm and ∼ 4 ppm, we extract a spin diffusion length which shows this suppression below 30 K only in the presence of the Kondo effect. We have calculated the spin-relaxation rate and isolated the contribution from magnetic impurities. We find the spin-flip probability of a magnetic impurity to be 34%. Our analysis demonstrates the dominant role of Kondo scattering in spin relaxation, even in low concentrations of order 1 ppm, and hence illustrates its importance to the reduction in spin diffusion length observed by ourselves and others.

show abstract

Room-Temperature Electron Spin Transport in a Highly Doped Si Channel

Cited by 209 publications

References 17 publications

Gate-tunable black phosphorus spin valve with nanosecond spin lifetimes

Gate-tunable black phosphorus spin valve with nanosecond spin lifetimes

Strained germanium for applications in spintronics

Spin relaxation through Kondo scattering in Cu/Py lateral spin valves

Contact Info

Product

Resources

About