Spin dynamics in small conductors probed by current fluctuations

2014 Fiscal Year Final Research Report

• Project/Area Number: 25887037
• Research Category: Grant-in-Aid for Research Activity Start-up
• Allocation Type: Single-year Grants
• Research Field: Condensed matter physics I
• Research Institution: Osaka University
• Principal Investigator: ARAKAWA TOMONORI 大阪大学, 理学(系)研究科(研究院), 助教 (00706757)
• Project Period (FY): 2013-08-30 – 2015-03-31
• Keywords: メゾスコピック系 / スピントロニクス / ショット雑音 / スピン流 / スピン蓄積

Outline of Final Research Achievements

How can we electrically detect spin current? In 1918, Schottky argued that the electric flow in a vacuum tube shows peculiar fluctuation whose amplitude is proportional to elementary charge and to the mean current. This is shot noise, a direct consequence of the discreteness of the electric charge. Now, consider the discreteness of spin. By using a spin-valve-type solid-state device, we successfully detected the shot noise induced by a　non-equilibrium spin accumulation. The observed shot noise is proportional to the spin current, yielding a spin analogue of Schottky's argument. Our experimental demonstration could open a novel way to approach non-equilibrium spin phenomena like spintronics.

Free Research Field

メゾスコピック系における量子輸送現象