The 76th JSAP Autumn Meeting, 2015

Presentation information

Symposium

Symposium » The New Spintronics Phenomena and Potential for the Applications

[15p-3A-1~7] The New Spintronics Phenomena and Potential for the Applications

Tue. Sep 15, 2015 1:15 PM - 5:15 PM 3A (International Conference Room)

座長:金井 駿(東北大),中根 了昌(東大工)

1:15 PM - 1:45 PM

[15p-3A-1] Spin-dependent Transport and Nonequilibrium Current Fluctuations in Mesoscopic Systems

〇Kensuke Kobayashi1 (1.Osaka Univ.)

Keywords:spin-dependent transport,current fluctuation (current noise),mesoscopic systems

Since 1980s mesoscopic conductors have been serving as an ideal test stage to investigate the quantum scattering problem, as electron transport through a single quantum site can be precisely probed in electric measurements. The Landauer-Büttiker formalism embodies this advantage of mesoscopic physics, and it has been successfully applied to many mesoscopic conductors such as electron interferometer, quantum point contact, and quantum dot (artificial atom), through which the mesoscopic physics has been established. Not only the current, but also the current fluctuation (or equivalently current noise) has been an important topic in this field.
Here we report the observation of excess shot noise connected with a spin current which is induced by a nonequilibrium spin accumulation in an all-semiconductor lateral spin-valve device. We find that this excess shot noise is proportional to the spin current. Additionally, we determine quantitatively the spin-injection-induced electron temperature by measuring the current noise. Our experiments show that spin accumulation driven shot noise provides a novel means of investigating nonequilibrium spin transport [T. Arakawa, et al. Phys. Rev. Lett. 114, 016601 (2015)].