论文标题
掺杂的AA堆积双层石墨烯中的可调等离子模式
Tunable plasmon modes in doped AA-stacked bilayer graphene
论文作者
论文摘要
我们在最近的邻邻紧密结合和随机相近似中研究了掺杂的AA堆叠双层石墨烯（BLG）中的等离子模式。我们获得了极化函数的封闭分析表达式，用于获得声学和光学等离子体模式的低能分散关系和数值结果。我们的结果揭示了AA堆叠BLG用作可调等离子设备的潜力。特别是我们发现，长波长的声学等离子体分散为$ω_ {+} \ of of sqrt {max（|μ|，t_ {1}）q} $，具有相位空间，它们缩小并消失了，因为化学势可以使内层跳跃的能量消失，从而阻止了长期存在的plasecon plasson plasson。此外，我们表明AA堆叠的BLG支持仅在条件时仅在$（1+ \ frac {g_σg_{v} e^{2} t_ {1} d} {κV_{κV_{f}^{2}}} \ frac {|μ|}表明即使在长波长极限下，降含量AA粘液BLG中光学等离子体的阻尼也是如此。我们还发现，光学等离子体模式分散为$ω_ { - } \近似δ+cq^{2} $，可以通过调谐化学电位来调整常数。
We study plasmon modes in doped AA-stacked bilayer graphene (BLG) within the nearest-neighbor tight-binding and the random phase approximation. We obtain closed analytical expressions for the polarizability function which are used to obtain the low-energy dispersion relations of and the numerical results for both acoustic and optical plasmon modes. Our result reveal the potential of AA-stacked BLG to be used as a tunable plasmonic device. In particular we find that the long-wavelength acoustic plasmon disperse as $ω_{+}\approx\sqrt{max(|μ|,t_{1})q}$ with a phase space which shrinks and vanishes as the chemical potential approaches the interlayer hopping energy, preventing the existence of long-lived acoustic plasmon. Furthermore, we show that AA-stacked BLG support coherent optical plasmon only when the condition $(1+\frac{g_σg_{v}e^{2}t_{1}d}{κv_{F}^{2}}\frac{|μ|}{t_{1}})^{1/2}<\frac{|μ|}{t_{1}}$ is satisfied, specially indicating Landau damping of the optical plasmon in undoped AA-staked BLG even at long-wavelength limit. We also find that the optical plasmon mode disperses as $ω_{-}\approx Δ+Cq^{2}$ with constants that can be tuned by tuning the chemical potential.
