Long-range Self-assembly via the Mutual Lorentz Force of Plasmon Radiation

Intrinsically ultrastrong plasmon-exciton interactions in crystallized films of carbon nanotubes

In cavity quantum electrodynamics, optical emitters that are strongly coupled to cavities give rise to polaritons with characteristics of both the emitters and the cavity excitations. We show that carbon nanotubes can be crystallized into chip-scale, two-dimensionally ordered films and that this new material enables intrinsically ultrastrong emitter-cavity interactions: rather than interacting with external cavities, nanotube excitons couple to the near-infrared plasmon resonances of the nanotubes themselves. Our polycrystalline nanotube films have a hexagonal crystal structure, ~25 nm domains…

外延石墨烯微米薄片中的等离激元-等离激元相互作用及缓冲层的作用

Plasmon-plasmon interaction and the role of buffer in epitaxial graphene micro-flakes

本文通过远红外磁等离激元吸收、拉曼成像和原子力显微镜，揭示外延石墨烯平移对称性破缺源于自发形成的微米薄片，并阐明缓冲层通过界面态库仑屏蔽与等离激元耦合共同导致纳米带中的异常红移。

Tunable nonlinear graphene metasurfaces

We introduce the concept of nonlinear graphene metasurfaces employing the controllable interaction between a graphene layer and a planar metamaterial. Such hybrid metasurfaces support two types of subradiant resonant modes, asymmetric modes of structured metamaterial elements ("metamolecules") and graphene plasmons exhibiting strong mutual coupling and avoided dispersion crossing. High tunability of graphene plasmons facilitates strong interaction between the subradiant modes, modifying the spectral position and lifetime of the associated Fano resonances. We demonstrate that strong resonant in…

Molecular Patterning and Directed Self-Assembly of Gold Nanoparticles on GaAs

The ability to create micro/nano patterns of organic self-assembled monolayers on semiconductor surfaces is crucial for fundamental studies and applications in a number of emerging fields in nanoscience. Here, we demonstrate the patterning of thiol molecular SAMs on oxide-free GaAs surface by dip-pen nanolithography and micro-contact printing, facilitated by a process of surface etching and passivation of the GaAs. A quantitative analysis on the molecular diffusion on GaAs was conducted by examining the writing of nanoscale dot and line patterns by DPN, which agrees well with surface diffusion…

Bottom-up fabrication of highly ordered metal nanostructures by hierarchical self-assembly

In a hierarchical nanopatterning routine relying exclusively on self-assembly processes we combine crystal surface reconstruction, microphase separation of copolymers, and selective metal diffusion to produce monodisperse metal nanostructures in highly regular arrays covering areas of square centimeters. In-situ GISAXS during Fe nanostructure formation evidences the outstanding structural order in the self-assembling system and hints at possibilities of sculpting nanostructures by external process parameters. Thus, we demonstrate that nanopatterning via self-assembly is a competitive alternati…

Hierarchical self-assembly of nanoparticles for optical metamaterials

Hierarchical self-assembly arranges nanostructures at different length scales. It gradually becomes an effective method of fabricating artificial metamaterials from composite nanostructures tailored for a particular response. Hierarchical self-assembly overcomes shortcomings of "top-down" methods by significantly reducing fabrication time and making it possible to form bulk materials. Here we report an application of hierarchical self-assembly of metal nanoparticles for the creation of the first isotropic optical metamaterial with strong artificial magnetism in blue light. We have used colloid…

Charge induced coherence between intersubband plasmons in a quantum structure

In this work we investigate a low dimensional semiconductor system, in which the light-matter interaction is enhanced by the cooperative behavior of a large number of dipolar oscillators, at different frequencies, mutually phase locked by Coulomb interaction. We experimentally and theoretically demonstrate that, owing to this phenomenon, the optical response of a semiconductor quantum well with several occupied subbands is a single sharp resonance, associated to the excitation of a bright multisubband plasmon. This effect illustrates how the whole oscillator strength of a two-dimensional syste…

Interaction of magnons with plasmons in a system of antiferromagnetic insulators coupled to a superconductor microwave cavity through the interfacial exchange interaction

A superconductor can interact with magnets through the magnetic field which is induced by the supercurrent. However, this interaction is rather weak and requires relatively large magnets to reach a sizable hybridization of microwave electromagnetic modes with magnons. The size of the device can be drastically reduced by means of the large interfacial exchange interaction between spins in a magnet and a superconductor. In the spin-orbit coupled superconductor this interaction can be transmitted to the s-wave condensate through a mixing of triplet and singlet Cooper pairs. In this paper we theor…

Temporal Quantum Control with Graphene

We introduce a novel strategy for controlling the temporal evolution of a quantum system at the nanoscale. Our method relies on the use of graphene plasmons, which can be electrically tuned in frequency by external gates. Quantum emitters (e.g., quantum dots) placed in the vicinity of a graphene nanostructure are subject to the strong interaction with the plasmons of this material, thus undergoing time variations in their mutual interaction and quantum evolution that are dictated by the externally applied gating voltages. This scheme opens a new path towards the realization of quantum-optics d…