论文标题
在局部耗散存在下非线性运输
Nonlinear transport in the presence of a local dissipation
论文作者
论文摘要
我们表征了连接到两端连接到储层的耗散一维晶格中的粒子传输，粒子损失和非平衡稳态。自由屈服的储层固定在不同的化学电位上，从而产生颗粒的运输。耗散是由于局部粒子损失作用在中心位点。我们使用Keldysh描述计算在非线性状态下电压的保守电流和损耗电流作为电压的功能。电流显示出类似阶梯的特征，这些特征会受到局部损失的不同影响：步骤要么平滑，几乎不受影响，甚至增强，具体取决于单粒子本征态的空间对称性，从而产生了步骤。此外，我们计算链中的粒子密度和动量分布。在有限的电压下，可能会发生两个费米动量，并连接到有损位点两侧的弗里德尔振荡的不同波长。我们发现波长是由储层中的化学势而不是晶格中的平均密度确定的。
We characterize the particle transport, particle loss, and nonequilibrium steady states in a dissipative one-dimensional lattice connected to reservoirs at both ends. The free-fermion reservoirs are fixed at different chemical potentials, giving rise to particle transport. The dissipation is due to a local particle loss acting on the center site. We compute the conserved current and loss current as functions of voltage in the nonlinear regime using a Keldysh description. The currents show step-like features which are affected differently by the local loss: The steps are either smoothened, nearly unaffected, or even enhanced, depending on the spatial symmetry of the single-particle eigenstate giving rise to the step. Additionally, we compute the particle density and momentum distributions in the chain. At a finite voltage, two Fermi momenta can occur, connected to different wavelengths of Friedel oscillations on either side of the lossy site. We find that the wavelengths are determined by the chemical potentials in the reservoirs rather than the average density in the lattice.
