Fluctuations of the Local Density of States Probe Localized Surface Plasmons on Disordered Metal Films

Krachmalnicoff, Valentina; Castanié, E.; Wilde, Yannick De; Carminati, Rémi

doi:10.1103/physrevlett.105.183901

Cited by 156 publications

(171 citation statements)

References 32 publications

Supporting

Mentioning

163

Contrasting

Order By: Relevance

“…m f R S D . 40 At the percolation threshold, the 2D bond percolation model used to design the lithographic networks is known to have a fractal dimension D ¼ 91/48, 40 a typical value for 2D systems; similar values have been found also in semi-continuous lms 33,43 even if using a different denition of the fractal dimension. Above the percolation threshold, the gold network evolves towards a continuous uniform lm with Euclidean dimension D ¼ 2 while, for very small values of p, the network consists of isolated antennas with no fractal properties and again Euclidean dimension D ¼ 2.…”

Section: Topological Propertiesmentioning

confidence: 95%

Percolating plasmonic networks for light emission control

et al. 2015

View full text Add to dashboard Cite

Optical nanoantennas have revolutionised the way we manipulate single photons emitted by individual light sources in a nanostructured photonic environment. Complex plasmonic architectures allow for multiscale light control by shortening or stretching the light wavelength for a fixed operating frequency, meeting the size of the emitter and that of propagating modes. Here, we study self-assembled semi-continuous gold films and lithographic gold networks characterised by large local density of optical state (LDOS) fluctuations around the electrical percolation threshold, a regime where the surface is characterised by large metal clusters with fractal topology. We study the formation of plasmonic networks and their effect on light emission from embedded fluorescent probes in these systems. Through fluorescence dynamics experiments we discuss the role of global long-range interactions linked to the degree of percolation and to the network fractality, as well as the local near-field contributions coming from the local electro-magnetic fields and the topology. Our experiments indicate that local properties dominate the fluorescence modification.

show abstract

Section: Topological Propertiesmentioning

confidence: 95%

Percolating plasmonic networks for light emission control

et al. 2015

View full text Add to dashboard Cite

show abstract

“…The other type of experiment, such as STM, probes the local energy level or the LDOS. 9,[16][17][18][19]26 The majority of experiments on both graphene and conventional 2DEG's suggest that Gaussian LS's appear in global measurements while Lorentzian LS's appear in local measurements. This is a plausible conjecture because almost all electronic states in two-dimensional QHE systems are localized except the one at the center of each LS (necessary for observing QHE).…”

mentioning

confidence: 99%

Shape of the Landau subbands in disordered graphene

et al. 2011

View full text Add to dashboard Cite

The question of why different experiments obtain different shapes of Landau subbands of two-dimensional electron gases (2DEG's) is investigated. In particular, we consider disordered graphene within the tight-binding formulation in a high magnetic field and in the presence of impurity potentials of a finite interaction range. It is found that the shape of the total density of states (DOS) of Landau subbands is well described by a Gaussian function, while the shape of the local density of states (LDOS) can be fitted to either a simple Lorentzian function or a sum of several Lorentzian functions. This finding explains well why the experiments that measure the DOS of a Landau subband appear to be Gaussian, and those experiments that are sensitive to the LDOS can only be fitted well by Lorentzian functions. Thus, our results provide a natural explanation to this long-standing puzzle involving 2DEG's in the quantum Hall regime. Graphene has attracted a lot of attention due to its remarkable properties and its potential applications in nanoelectronics. 1 Its electronic properties are mainly due to its two-dimensional nature and the fact that the low-energy excitations are governed by the massless Dirac equation, 2 confirmed by the interesting, uneven Landau level (LL) distribution that varies with both the square root of the magnetic field B and the LL index n: E n = sgn(n) 2ehv 2 F |n|B, where v F , e, andh are the Fermi velocity, electron charge, and the Planck constant, respectively. This emblematic LL spectrum and its characteristic zero-energy state (n = 0) are directly related to the anomalous quantum Hall effect (QHE) in graphene. 3 Many efforts have been made to determine the electronic properties of the disorder-broadened Landau subbands (LS's). However, the shape of both the total density of states (DOS) and the local DOS (LDOS) of an LS of graphene is a controversial issue in the literature. Historically, it has generally been believed that the shape of the DOS of LS's in a conventional two-dimensional electron gas (2DEG) is Gaussian-like, 4,5 but experiments seem to present a different picture. Initially, this consensus was supported by careful measurements of specific heat, 6 magnetization, 7 and magnetocapacitance 8 on GaAs-Ga x Al 1−x As heterostructures. However, a recent scanning-tunneling-microscopy-scanningtunneling-spectroscopy (STM-STS) measurement on conventional 2DEG's of the n-InSb(110) ] surface, 9 as well as the cyclotron resonance (CR) absorption line shape on conventional 2DEG's, 10,11 observed a Lorentzian shape of an LS. The situation for disordered graphene is similar. All CR 13-15 and STM-STS 16-19 measurements suggested clearly a Lorentzian shape for an LS. However, recent magnetocapacitance experiments produced conflicting results: In one experiment, 20 an LS could be fitted well by the Lorentzian functions, while another experiment 21 observed a Gaussian shape for an n = 0 LS. On the theoretical side, the DOS of an LS of graphene is initially found to be Gaussian-like. [22][23][24] C...

show abstract

“…Founding experiments on modified emission dynamics in random media employed ensembles of emitters [14][15][16] , which do not enable extracting ρ(r0) in a complex medium and therefore the C0 correlation could not be obtained. Experiments on single emitters have so far concentrated on cavity quantumelectrodynamics studies in one-dimensional disordered photonic crystal waveguides 17 , where the collection of statistics required for obtaining the C0 correlation could not be obtained.…”

mentioning

confidence: 99%

Nonuniversal Intensity Correlations in a Two-Dimensional Anderson-Localizing Random Medium

et al. 2012

View full text Add to dashboard Cite

Complex dielectric media often appear opaque because light traveling through them is scattered multiple times. Although the light scattering is a random process, different paths through the medium can be correlated encoding information about the medium. Here, we present spectroscopic measurements of nonuniversal intensity correlations that emerge when embedding quantum emitters inside a disordered photonic crystal that is found to Anderson-localize light. The emitters probe in-situ the microscopic details of the medium, and imprint such near-field properties onto the farfield correlations. Our findings provide new ways of enhancing light-matter interaction for quantum electrodynamics and energy harvesting, and may find applications in subwavelength diffuse-wave spectroscopy for biophotonics. PACS numbers: (42.25.Dd, 42.25.Fx, 46.65.+g, 42.70.Qs) Correlations are of paramount importance in science and technology and offer fundamental insight into disparate disciplines ranging from establishing the role of inflation in the early universe 1 , through mesocopic transport of electrons and photons in complex media 2 , to the non-locality of quantum mechanics observed at the microscopic scale 3 . In photonics, recording correlation functions provides a powerful method of revealing information of the quantum state of light 4 and correlations may be exploited for imaging beyond the classical diffraction limit 5 . The emerging field of nanophotonics promises a number of new applications for controlling and manipulating light. However, unavoidable inhomogeneities lead to random multiple scattering that requires a statistical description. Surprisingly, such multiple scattering can give rise to pronounced correlations between different propagation paths through the complex medium, at variance with the intuitive perception that random scattering fully scrambles all information. Such correlations can be either of classical 6 or quantum 7 character and are traditionally universal, i.e., they depend solely on a single parameter, the universal conductance, and are independent of the microscopic details of the medium. Placing a light source inside the medium creates a fundamentally new situation. In this case, nonuniversal correlations in the far field have been predicted 8 that depend sensitively on the local environment of the embedded emitter 9 , and thus can be employed for probing the local properties of a complex medium. Consequently, recording the nonuniversal correlation function has been proposed as a novel method for in-situ spectroscopy with ultra-high resolution in a complex and disordered medium 10 , and algorithms have been proposed for imaging a source in an opaque medium from measurements of the local electromagnetic field density 11 . In this Letter, we measure for the first time the nonuniversal correlations generated by single dipole emitters in a strongly scattering random medium.Figure 1(a) illustrates an intensity speckle pattern generated by a dipole source embedded in a disordered photonic crystal membra...

show abstract

Fluctuations of the Local Density of States Probe Localized Surface Plasmons on Disordered Metal Films

Cited by 156 publications

References 32 publications

Percolating plasmonic networks for light emission control

Percolating plasmonic networks for light emission control

Shape of the Landau subbands in disordered graphene

Nonuniversal Intensity Correlations in a Two-Dimensional Anderson-Localizing Random Medium

Contact Info

Product

Resources

About