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Thermal spin injection and accumulation in CoFe/MgO/n-type Ge contacts.

ABSTRACT: Understanding the interplay between spin and heat is a fundamental and intriguing subject. Here we report thermal spin injection and accumulation in CoFe/MgO/n-type Ge contacts with an asymmetry of tunnel spin polarization. Using local heating of electrodes by laser beam or electrical current, the thermally-induced spin accumulation is observed for both polarities of the temperature gradient across the tunnel contact. We observe that the magnitude of thermally injected spin signal scales linearly with the power of local heating of electrodes, and its sign is reversed as we invert the temperature gradient. A large Hanle magnetothermopower (HMTP) of about 7.0% and the Seebeck spin tunneling coefficient of larger than 0.74?meV K(-1) are obtained at room temperature.

SUBMITTER: Jeon KR

PROVIDER: S-EPMC3520029 | biostudies-literature | 2012

REPOSITORIES: biostudies-literature

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Thermal spin injection and accumulation in CoFe/MgO/n-type Ge contacts.

Jeon Kun-Rok KR Min Byoung-Chul BC Park Seung-Young SY Lee Kyeong-Dong KD Song Hyon-Seok HS Park Youn-Ho YH Jo Young-Hun YH Shin Sung-Chul SC

Scientific reports 20121212

Understanding the interplay between spin and heat is a fundamental and intriguing subject. Here we report thermal spin injection and accumulation in CoFe/MgO/n-type Ge contacts with an asymmetry of tunnel spin polarization. Using local heating of electrodes by laser beam or electrical current, the thermally-induced spin accumulation is observed for both polarities of the temperature gradient across the tunnel contact. We observe that the magnitude of thermally injected spin signal scales linearl ...[more]

PMID: 23236584

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