Bahrami Mousa, Vasilopoulos Panagiotis
Bita Quantum AI Inc., 2021 Av. Atwater, Montréal, QC H3H 2P2, Canada.
Department of Physics, Concordia University, 7141 Sherbrooke Ouest, Montreal, QC H4B 1R6, Canada.
Nanomaterials (Basel). 2022 Aug 19;12(16):2861. doi: 10.3390/nano12162861.
We study the effect of the phase-change material VO2 on plasmons in metallic arm-chair graphene nanoribbons (AGNRs) within the random-phase approximation (RPA) for intra- and inter-band transitions. We assess the influence of temperature as a knob for the transition from the insulating to the metallic phase of VO2 on localized and propagating plasmon modes. We show that AGNRs support localized and propagating plasmon modes and contrast them in the presence and absence of VO2 for intra-band (SB) transitions while neglecting the influence of a substrate-induced band gap. The presence of this gap results in propagating plasmon modes in two-band (TB) transitions. In addition, there is a critical band gap below and above which propagating modes have a linear negative or positive velocity. Increasing the band gap shifts the propagating and localized modes to higher frequencies. In addition, we show how the normalized Fermi velocity increases plasmon modes frequency.
我们在随机相位近似（RPA）下研究了相变材料VO₂对金属扶手椅型石墨烯纳米带（AGNRs）中带内和带间跃迁等离激元的影响。我们将温度作为一个调节旋钮，评估VO₂从绝缘相转变为金属相时对局域和传播等离激元模式的影响。我们表明，AGNRs支持局域和传播等离激元模式，并在忽略衬底诱导带隙影响的情况下，对比了带内（SB）跃迁中有无VO₂时的这些模式。这个带隙的存在导致了双带（TB）跃迁中的传播等离激元模式。此外，存在一个临界带隙，在其之下和之上，传播模式具有线性负速度或正速度。增大带隙会使传播和局域模式向更高频率移动。此外，我们还展示了归一化费米速度如何提高等离激元模式频率。
