arXiv 0902.23892009-02cond-mat.mes-hallcond-mat.mtrl-sci

Charge pumping and the colored thermal voltage noise in spin valves

Jiang Xiao, Gerrit E. W. Bauer, Sadamichi Maekawa, Arne Brataas

备注：: 9 pages, 2 figures
发表信息：: Phys. Rev. B 79, 174415 (2009)
DOI：: 10.1103/PhysRevB.79.174415

英文摘要：

Spin pumping by a moving magnetization gives rise to an electric voltage over a spin valve. Thermal fluctuations of the magnetization manifest themselves as increased thermal voltage noise with absorption lines at the ferromagnetic resonance frequency and/or zero frequency. The effect depends on the magnetization configuration and can be of the same order of magnitude as the Johnson-Nyquist thermal noise. Measuring colored voltage noise is an alternative to ferromagnetic resonance experiments for nano-scale ferromagnetic circuits.

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