We calculate the plasmon frequency and damping rate of plasma oscillations in a spin-polarized BLG system. Using the long wavelength approximation for dynamical dielectric function, we obtain an analytical expression for plasmon frequency showing that the degree of spin polarization P has negligible effect on the long wavelength plasmon frequency. Numerical calculations demonstrate that the degree of spin polarization affects slightly (strongly) plasmon frequency at small (large) wave-vectors and the maximum value of damping rate increases with increasing P. We also study the effects of carrier density and substrate dielectric constant on plasmon properties for different value of spin polarization. The numerically calculated critical wave-vector, at which the plasmon dispersion curve hits the edge of electron-hole continuum, decreases with P and can be used to determine experimentally the degree of spin polarization.

中文翻译：

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自旋极化双层石墨烯中的集体激发

我们计算了自旋极化 BLG 系统中等离子体振荡的等离子体频率和阻尼率。使用动态介电函数的长波长近似，我们获得了等离子体频率的解析表达式，表明自旋极化程度 P 对长波长等离子体频率的影响可以忽略不计。数值计算表明，自旋极化程度对小（大）波矢量的等离子体频率有轻微（强烈）影响，并且阻尼率的最大值随着 P 的增加而增加。我们还研究了载流子密度和衬底介电常数对等离子体的影响不同自旋极化值的特性。数值计算的临界波矢量，在该处等离子体色散曲线撞击电子 - 空穴连续体的边缘，