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![Measuring the Spin-Lattice Relaxation Magnetic Field Dependence of Hyperpolarized [1-13C]pyruvate](/_next/image?url=https%3A%2F%2Fcloudfront.jove.com%2FCDNSource%2Fteasers%2F59399.jpg&w=3840&q=50)
Measuring the Spin-Lattice Relaxation Magnetic Field Dependence of Hyperpolarized [1-13C]pyruvate
Published on: September 13, 2019
Metal-free magnetism, spin-dependent Seebeck effect, and spin-Seebeck diode effect in armchair graphene nanoribbons
Xiao-Qin Tang1, Xue-Mei Ye1, Xing-Yi Tan2
1School of Science, Hubei University for Nationalities, Enshi, 445000, People's Republic of China.
Abstract:
Metal-free magnetism and spin caloritronics are at the forefront of condensed-matter physics. Here, the electronic structures and thermal spin-dependent transport properties of armchair graphene nanoribbons (N-AGNRs), where N is the ribbon width (N = 5-23), are systematically studied. The results show that the indirect band gaps exhibit not only oscillatory behavior but also periodic characteristics with E 3p > E3p+1 > E3p+2 (E 3p , E3p+1 and E3p+2 are the band gaps energy) for a certain integer p, with increasing AGNR width. The magnetic ground states are ferromagnetic (FM) with a Curie temperatures (T C ) above room temperature. Furthermore, the spin-up and spin-down currents with opposite directions, generated by a temperature gradient, are almost symmetrical, indicating the appearance of the perfect spin-dependent Seebeck effect (SDSE). Moreover, thermally driven spin currents through the nanodevices induced the spin-Seebeck diode (SSD) effect. Our calculation results indicated that AGNRs can be applied in thermal spin nanodevices.
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