Dreher Pascal, Janoschka David, Neuhaus Alexander, Frank Bettina, Giessen Harald, Horn-von Hoegen Michael, Meyer Zu Heringdorf Frank-J
Faculty of Physics and Center for Nanointegration, Duisburg-Essen (CENIDE), University of Duisburg-Essen, 47048 Duisburg, Germany.
4th Physics Institute, Research Center SCoPE, and Integrated Quantum Science and Technology Center, University of Stuttgart, 70569 Stuttgart, Germany.
Nanophotonics. 2022 Aug 2;11(16):3687-3694. doi: 10.1515/nanoph-2022-0284. eCollection 2022 Sep.
Spectroscopic photoemission microscopy is used to detect and quantify a ponderomotive shift in the energy of electrons that are emitted from a surface plasmon polariton focus. The focus is formed on an atomically flat Au(111) surface by an Archimedean spiral and is spatiotemporally separated from the circularly polarized light pulse used to excite the spiral. A spectroscopic analysis of electrons emitted from the focus exhibits a peaked above-threshold electron emission spectrum. From the shift of the peaks as function of laser power the field strength of the surface plasmon polariton was quantitatively determined free parameters. Estimations of the Keldysh parameter = 4.4 and the adiabaticity parameter = 4700 indicate that electron emission occurs in a regime of multiplasmon absorption and nonlocalized surface plasmon fields.
光谱光发射显微镜用于检测和量化从表面等离激元极化子焦点发射的电子能量中的有质动力位移。该焦点由阿基米德螺旋在原子级平整的Au(111)表面形成，并与用于激发螺旋的圆偏振光脉冲在时空上分离。对从焦点发射的电子进行光谱分析，呈现出一个峰值超阈值电子发射光谱。根据峰值随激光功率的变化，定量确定了表面等离激元极化子的场强，无自由参数。对凯尔迪什参数γ = 4.4和绝热参数α = 4700的估计表明，电子发射发生在多等离子体吸收和非局域表面等离激元场的区域。
