Thermoelectric spin voltage in graphene 2017/12/22 - PowerPoint PPT Presentation

Thermoelectric spin voltage in graphene 张志斌 北京大学 物理学院 2017/12/22 2017/12/22

O u t l i n e Spin Hall Effect Seebeck Effect Inverse Spin Hall Effect Spin Seebeck Effect ~ 2 ~

Spin Hall Effect & Inverse Spin Hall Effect Input charge current Output charge current Output spin current Input spin current ~ 3 ~

Seebeck Effect ∆𝑊 𝑇 = − Seebeck coefficient ∆𝑈 ~ 4 ~

Spin Seebeck Effect Scenario for the spin Seebeck effect: In the spin sector, a magnet works in the same way as a thermocouple Uchida et al. Nature 2008 ~ 5 ~

Spin Seebeck Effect Ni 81 Fe 19 Pt Uchida et al. Nature 2008 ~ 6 ~

Thermoelectric spin voltage in graphene ~ 7 ~

Thermoelectric spin voltage in graphene holes electrons + − 𝑊 − = −∆𝑇∆𝑈 = −(𝑇 2 − 𝑇 1 ) ∆𝑈 ∆𝑇 = 𝑇 2 (𝑜 2 ) − 𝑇 1 (𝑜 1 ) 𝑊 𝑇 = 𝑊 𝑇 𝑇 Juan F. Sierra et al. Nature Nano 2017 ~ 8 ~

Thermoelectric spin voltage in graphene Spin injection and detection @ ferromagnetic electrodes Metal electrodes Juan F. Sierra et al. Nature Nano 2017 ~ 9 ~

Thermoelectric spin voltage in graphene Joule heating Joule heating Juan F. Sierra et al. Nature Nano 2017 ~ 10 ~

Thermoelectric spin voltage detection Juan F. Sierra et al. Nature Nano 2017 ~ 11 ~

Out-of-plane magnetic field Juan F. Sierra et al. Nature Nano 2017 ~ 12 ~

Thanks ~ 13 ~