International Center for Quantum Design of Functional Materials (ICQD), Hefei National Laboratory for Physical Sciences at the Microscale, and Synergetic Innovation Center of Quantum Information and Quantum Physics, University of Science and Technology of China , Hefei, Anhui 230026, China.
CAS Key Laboratory of Strongly-Coupled Quantum Matter Physics and Department of Physics, University of Science and Technology of China , Hefei, Anhui 230026, China.
Nano Lett. 2018 Feb 14;18(2):1373-1378. doi: 10.1021/acs.nanolett.7b05085. Epub 2018 Jan 19.
Quantum mechanical effects of single particles can affect the collective plasmon behaviors substantially. In this work, the quantum control of plasmon excitation and propagation in graphene is demonstrated by adopting the variable quantum transmission of carriers at Heaviside potential steps as a tuning knob. First, the plasmon reflection is revealed to be tunable within a broad range by varying the ratio γ between the carrier energy and potential height, which originates from the quantum mechanical effect of carrier propagation at potential steps. Moreover, the plasmon excitation by free-space photos can be regulated from fully suppressed to fully launched in graphene potential wells also through adjusting γ, which defines the degrees of the carrier confinement in the potential wells. These discovered quantum plasmon effects offer a unified quantum-mechanical solution toward ultimate control of both plasmon launching and propagating, which are indispensable processes in building plasmon circuitry.
单粒子的量子力学效应会显著影响集体等离激元行为。在这项工作中，通过采用海维赛德势阶处载流子的可变量子透射率作为调节旋钮，实现了对石墨烯中等离激元激发和传播的量子调控。首先，通过改变载流子能量与势高之比γ，可以在很宽的范围内调节等离激元反射，这源于载流子在势阶处传播的量子力学效应。此外，通过调节γ，还可以在石墨烯势阱中从完全抑制到完全激发自由空间光激发的等离激元，这定义了载流子在势阱中的束缚程度。这些被发现的量子等离激元效应为实现对等离激元激发和传播的终极控制提供了一个统一的量子力学解决方案，这是构建等离激元电路所必需的过程。
