,Enhanced spin-dependent thermopower in a double-quantum-dot sandwiched between two-dimensional elec

• 作 者: Feng Chi Zhen-Guo Fu Liming Liu Ping Zhang
• 机 构: School of Electronic and Information Engineering, University of Electronic Science and Technology of
• 出 处: 中国物理B（英文版）
• 发表日期: 2019年10期
• 关键词: quantum dot spin-dependent thermopower two-dimensional electron gases

We study the spin-dependent thermopower in a double-quantum-dot (DQD) embedded between the left and right two-dimensional electron gases (2DEGs) in doped quantum wells under an in-plane magnetic field.When the separation between the DQD is smaller than the Fermi wavelength in the 2DEGs,the asymmetry in the dots’ energy levels leads to pronounced quantum interference effects characterized by the Dicke line-shape of the conductance,which are sensitive to the properties of the 2DEGs.The magnitude of the thermopower,which denotes the generated voltage in response to an infinitesimal temperature difference between the two 2DEGs under vanishing charge current,will be obviously enhanced by the Dicke effect.The application of the in-plane magnetic field results in the polarization of the spin-up and spin-down conductances and thermopowers,and enables an efficient spin-filter device in addition to a tunable pure spin thermopower in the absence of its charge counterpart.