Amiranashvili Sh, Yu M Y, Stenflo L
Department of Theoretical Physics, General Physics Institute, Moscow 119991, Russia.
Phys Rev E Stat Nonlin Soft Matter Phys. 2003 Jan;67(1 Pt 2):016408. doi: 10.1103/PhysRevE.67.016408. Epub 2003 Jan 29.
An analytical model for breathing oscillations in a nonuniform non-neutral plasma slab is developed. The plasma is relatively small and warm with the smallest dimension only of several Debye lengths. Nonuniformity in the equilibrium results in a frequency shift associated with pressure and boundary effects. The plasma size and temperature, being related to the frequency shift, can therefore be evaluated from frequency measurements. In particular, for small nonuniform plasmas the frequency of the breathing mode is twice that predicted by the cold fluid theory. Nonlinear oscillations are also considered and the pressure is shown to have an important effect on the dynamics. Analytical solutions for linear and nonlinear oscillations are obtained and compared with that from one-dimensional particle-in-cell simulations. Good agreement is found.
建立了一个非均匀非中性等离子体平板中呼吸振荡的解析模型。该等离子体相对较小且温度较高，其最小尺寸仅为几个德拜长度。平衡态的不均匀性导致与压力和边界效应相关的频率偏移。因此，与频率偏移相关的等离子体尺寸和温度可通过频率测量来评估。特别地，对于小的非均匀等离子体，呼吸模式的频率是冷流体理论预测值的两倍。还考虑了非线性振荡，并且表明压力对动力学有重要影响。获得了线性和非线性振荡的解析解，并与一维粒子模拟结果进行了比较。结果发现二者吻合良好。
