Nano- and microstructured materials for in vitro studies of the physiology of vascular cells

• Alexandra M. Greiner,
• Adria Sales,
• Hao Chen,
• Sarah A. Biela,
• Dieter Kaufmann and
• Ralf Kemkemer

Beilstein J. Nanotechnol. 2016, 7, 1620–1641, doi:10.3762/bjnano.7.155

• a different work, a plasmon was used to pattern a photoresist layer by means of NSOM (near-field scanning optical microscopy). A lateral resolution of about 50 nm was achieved, with a fabrication speed of ca 10 mm/s [65]. Nanoimprint lithography (NIL) is a low-cost nanopatterning technique for 2D

Localized surface plasmons in structures with linear Au nanoantennas on a SiO₂/Si surface

• Ilya A. Milekhin,
• Sergei A. Kuznetsov,
• Ekaterina E. Rodyakina,
• Alexander G. Milekhin,
• Alexander V. Latyshev and
• Dietrich R. T. Zahn

Beilstein J. Nanotechnol. 2016, 7, 1519–1526, doi:10.3762/bjnano.7.145

• nanoantenna coincide with the frequency of the exciting electromagnetic radiation. The LSPR yields a sharp increase of the local electromagnetic field magnitude near the nanoantenna surface that makes feasible to detect a small amount of alien substances located in the near field region of the nanoantenna [8

• plasmon–phonon coupling are to be expected. Indeed, as it was is shown in [31], such a coupling may drastically increase (by a factor of 200) the scattering intensity in the near field of the metal (Pt) tip of an atomic force microscope at frequencies of the SiC surface optical (SO) phonons. The results

• 12.5–13.9 nm and 14.4–16.6 nm for hSiO2 = 0 and 100 nm, respectively. It is noteworthy that functionally the E-decay behavior is fitted well not by a single exponent but by a sum of two exponents P1•exp(−z/δ1) and P2•exp(−z/δ2), which describe short-range (near-field) and long-range (far-field

Tunable longitudinal modes in extended silver nanoparticle assemblies

• Serene S. Bayram,
• Klas Lindfors and
• Amy Szuchmacher Blum

Beilstein J. Nanotechnol. 2016, 7, 1219–1228, doi:10.3762/bjnano.7.113

• valence electrons. For example, localized plasmon resonance arises from the restoring force exerted on electrons driven by an external field, which results in field amplification in the near-field zone at the particle surface. Alterations in particle size and shape cause a frequency shift in the localized

• of modern applications in surface-enhanced Raman spectroscopy (SERS), optical sensing and emission enhancement of molecules residing in the near field [33][34]. In addition to applications in spectroscopy, plasmonic interactions may also be exploited in other light-based devices. The miniaturization

The role of morphology and coupling of gold nanoparticles in optical breakdown during picosecond pulse exposures

• Yevgeniy R. Davletshin and
• J. Carl Kumaradas

Beilstein J. Nanotechnol. 2016, 7, 869–880, doi:10.3762/bjnano.7.79

• resonance peaks of gold nanospheres towards the near infrared region. (This is useful in biological applications, where light has a good penetration depth) [5][16]. The use of plasmonic nanoparticles and the associated near-field enhancement has been used in applications based on the laser-induced breakdown

• a high near-field enhancement surrounding the gold nanorod (the near-field regime). At picosecond pulses with low irradiation fluence, nanoparticle-mediated LIB is dominated by photo-thermal emission due to the fast temperature increase of the electrons in the nanostructure. The lack of a detailed

• the picosecond regime is highly dependent on the optical near-field enhancement instead of nanoparticle size and absorption cross-section. The findings of this study will help in LIB-related fields to advance the understanding of nanoparticle–laser interactions, which will lead to the better design of

Optical absorption signature of a self-assembled dye monolayer on graphene

• Tessnim Sghaier,
• Sylvain Le Liepvre,
• Céline Fiorini,
• Ludovic Douillard and
• Fabrice Charra

Beilstein J. Nanotechnol. 2016, 7, 862–868, doi:10.3762/bjnano.7.78

• -3,4,9,10-diimide (PTCDI); scanning tunnelling microscopy; self-assembly; self-organization; Introduction Close-packed assemblies of dye molecules exhibit drastically altered photonic properties as compared with the isolated or diluted species [1]. These changes find their origin in near-field optical

Highly compact refractive index sensor based on stripe waveguides for lab-on-a-chip sensing applications

• Chamanei Perera,
• Kristy Vernon,
• Elliot Cheng,
• Juna Sathian,
• Esa Jaatinen and
• Timothy Davis

Beilstein J. Nanotechnol. 2016, 7, 751–757, doi:10.3762/bjnano.7.66

• propagating SP waves interfered with the incident light at the slit location causing modification of the light intensity transmitting through the slit. The intensity of the transmitted light carries information about the near-field interaction of the plasmon with the dielectric environment. The resolution of

Correlative infrared nanospectroscopic and nanomechanical imaging of block copolymer microdomains

• Benjamin Pollard and
• Markus B. Raschke

Beilstein J. Nanotechnol. 2016, 7, 605–612, doi:10.3762/bjnano.7.53

• . Here, we combine infrared vibrational scattering scanning near-field optical microscopy (IR s-SNOM) with force–distance spectroscopy for simultaneous characterization of both nanoscale optical and nanomechanical molecular properties through hybrid imaging. The resulting multichannel images and

• , hybrid imaging, near-field infrared spectroscopy, scanning probe microscopy; Introduction Functional soft-matter and polymer systems often exhibit novel phenomena due to nanoscale chemical heterogeneity and the resulting intermolecular interactions. Infrared vibrational scattering scanning near-field

• settings than the calibrated data shown below; the curve here is shown only to illustrate the different PF-QNM channels. In IR s-SNOM, conventional AFM is combined with an optical setup to focus and detect light from a tip-mediated near-field optical interaction confined to a nanoscale volume of the sample

Linear and nonlinear optical properties of hybrid metallic–dielectric plasmonic nanoantennas

• Mario Hentschel,
• Bernd Metzger,
• Bastian Knabe,
• Karsten Buse and
• Harald Giessen

Beilstein J. Nanotechnol. 2016, 7, 111–120, doi:10.3762/bjnano.7.13

• electric fields in nanoscale volumes around the nanoparticles. Due to the large resonant dipole moment, which is fundamentally connected to the large number of free conduction electrons, energy can be efficiently channeled from the far-field into the so-called near-field. As previously discussed [1][2

• ]. One can also transport energy on deep subwavelength length scales [5], create the plasmonic analogue of electromagnetically induced transparency (EIT) [6][7][8][9], and construct systems with tailorable near-field enhancement and confinement [10][11][12][13]. What is more, the resonant behavior of

• from metal-island films and microstructured silver films were shown to be related to the enhanced local near-field [22]. Gold and silver nanoparticles in water were shown to enable optical phase conjugation [23][24] with an order of magnitude enhanced optical Kerr coefficient when exciting the

Controlled graphene oxide assembly on silver nanocube monolayers for SERS detection: dependence on nanocube packing procedure

• Martina Banchelli,
• Bruno Tiribilli,
• Roberto Pini,
• Luigi Dei,
• Paolo Matteini and
• Gabriella Caminati

Beilstein J. Nanotechnol. 2016, 7, 9–21, doi:10.3762/bjnano.7.2

• in two orthogonal electron oscillations with respect to the surface plane when a strong near-field interaction between AgNPs occurs in the 2D array. The cubic geometry of the nanoparticles provides a large nanoparticle–substrate contact area, leading to efficient hybridization of dipolar (D) and

Near-field visualization of plasmonic lenses: an overall analysis of characterization errors

• Jing Wang,
• Yongqi Fu,
• Zongwei Xu and
• Fengzhou Fang

Beilstein J. Nanotechnol. 2015, 6, 2069–2077, doi:10.3762/bjnano.6.211

• University, 300072, P. R. China 10.3762/bjnano.6.211 Abstract Many factors influence the near-field visualization of plasmonic structures that are based on perforated elliptical slits. Here, characterization errors are experimentally analyzed in detail from both fabrication and measurement points of view

• . Some issues such as geometrical parameter, probe–sample surface interaction, misalignment, stigmation, and internal stress, have influence on the final near-field probing results. In comparison to the theoretical ideal case of near-field probing of the structures, numerical calculation is carried out

• nanophotonic devices. Keywords: characterization; nanofabrication; near-field; plasmonic lenses; plasmonic structures; Introduction The characteristics of nanophotonic devices that are based on surface plasmon polaritons (SPPs) are appealing because of the extraordinary transmission in free space [1][2][3][4

Mapping bound plasmon propagation on a nanoscale stripe waveguide using quantum dots: influence of spacer layer thickness

• Chamanei S. Perera,
• Alison M. Funston,
• Han-Hao Cheng and
• Kristy C. Vernon

Beilstein J. Nanotechnol. 2015, 6, 2046–2051, doi:10.3762/bjnano.6.208

• incoupling to the desired mode. A homogeneous thin layer of quantum dots was used to image the near field intensity of the propagating plasmons on the waveguide. We observed that the photoluminescence is quenched when the QD to metal surface distance is less than 10 nm. The optimised spacer layer thickness

• are a coherent oscillation of electrons in a metal [1]. Loosely bound electrons can combine with incoming photons and propagate along the metal/dielectric interface. These charge density waves create a strong near-field [1]. There is increasing demand for high speed data communication as well as

Superluminescence from an optically pumped molecular tunneling junction by injection of plasmon induced hot electrons

• Kai Braun,
• Xiao Wang,
• Andreas M. Kern,
• Hilmar Adler,
• Heiko Peisert,
• Thomas Chassé,
• Dai Zhang and
• Alfred J. Meixner

Beilstein J. Nanotechnol. 2015, 6, 1100–1106, doi:10.3762/bjnano.6.111

• scattering (TERS) [11][12] or gap mode near-field optical microscopy [13]. This technique has attracted great interest as a means for local Raman [14][15] or luminescence spectroscopy [16] with nanometer spatial resolution. Since efficient Raman scattering from molecules in the gap requires gap widths as

• scattered to the far field. While the gap modes plasmon resonance is very broad, exhibiting a quality factor of only Q ≈ 15, the resonantly stored energy in the optical near field in the gap is extremely well localized, in a volume having an upper limit of approximately 4 × 4 × 1 nm3 (see Figure S8

• the focus ΦL, the effective absorption coefficient, σ, taking into account the near-field effect and the lifetimes of the hot electrons, . From the incident radiation and the spectrally integrated emission intensity of the pure junction, σ is estimated to be on the order of 10−6. In our case, the hot

Electromagnetic enhancement of ordered silver nanorod arrays evaluated by discrete dipole approximation

• Guoke Wei,
• Jinliang Wang and
• Yu Chen

Beilstein J. Nanotechnol. 2015, 6, 686–696, doi:10.3762/bjnano.6.69

• nanoarrays and incident excitations will shine light on the optimal design of efficient SERS substrates and improved performance. Keywords: discrete dipole approximation (DDA); enhancement factor; near-field; silver nanorod array; surface-enhanced Raman scattering (SERS); Introduction Surface-enhanced

• powerful and flexible method for describing the far-field and near-field properties of targets with arbitrary geometries in a complex dielectric environment [19][20][21]. In DDA, the continuum target is represented by a finite cubic array of polarizable point dipoles, which is excited by an applied EM

• nanoarrays in vacuum employing the open-source code DDSCAT 7.2 developed by Draine and Flatau [19], which has the capability of performing efficient “near-field” calculations in and around the target by using fast-Fourier transform (FFT) methods [21]. The cubic grid spacing was 3 nm in all calculations. The

Tunable light filtering by a Bragg mirror/heavily doped semiconducting nanocrystal composite

• Ilka Kriegel and
• Francesco Scotognella

Beilstein J. Nanotechnol. 2015, 6, 193–200, doi:10.3762/bjnano.6.18

• frequency-dependent dielectric function of the bulk material (in this case approximated by the Drude model, Equations 8 and 9) and δi accounts for the volume fraction. Within this theory only far field interactions are taken into account, while near field interaction among the NCs are neglected. The

Exploring plasmonic coupling in hole-cap arrays

• Thomas M. Schmidt,
• Maj Frederiksen,
• Vladimir Bochenkov and
• Duncan S. Sutherland

Beilstein J. Nanotechnol. 2015, 6, 1–10, doi:10.3762/bjnano.6.1

• . The interesting and complex coupling between caps and hole arrays reveals the details of the field distribution for these simple to fabricate structures. Keywords: caps; colloidal lithography; hybridization; localized surface plasmon resonance; near field; SRO hole arrays; Introduction The

• strong electromagnetic fields can greatly enhance excitation and emission. Other uses of the enhanced local electromagnetic fields are as nanoscale lenses to carry out high resolution near field optical lithography [14], as antennas [15] for directing light emission at the nanoscale or increasing

• knowledge been previously reported. The coupling present in this simple to fabricate system can be used both to study dark SPP modes and/or for rational design of sensors through plasmon enhancement of optical processes (e.g., SERS or SEF) and/or engineering of the near field (lifting the SPP modes out of

Bright photoluminescence from ordered arrays of SiGe nanowires grown on Si(111)

• D. J. Lockwood,
• N. L. Rowell,
• A. Benkouider,
• A. Ronda,
• L. Favre and
• I. Berbezier

Beilstein J. Nanotechnol. 2014, 5, 2498–2504, doi:10.3762/bjnano.5.259

• occurring within the NWs. Keywords: bandgap; germanium; nanowires; near field; silicon; photoluminescence; Introduction Semiconductor nanowires (NWs) are thought of as promising building blocks for opto-electronic devices that exploit their novel electronic band structures generated by two-dimensional (2D

Inorganic Janus particles for biomedical applications

• Isabel Schick,
• Steffen Lorenz,
• Dominik Gehrig,
• Stefan Tenzer,
• Wiebke Storck,
• Karl Fischer,
• Dennis Strand,
• Frédéric Laquai and
• Wolfgang Tremel

Beilstein J. Nanotechnol. 2014, 5, 2346–2362, doi:10.3762/bjnano.5.244

• efficiencies. This influence was mainly ascribed to the enhanced dye absorption by the magnified near-field of Au nanoparticles and the plasmon-enhanced photocurrent generation (Figure 6c) [51]. Synthesis of inorganic Janus particles The synthesis of hetero-nanoparticles requires an even higher degree of

Localized surface plasmon resonances in nanostructures to enhance nonlinear vibrational spectroscopies: towards an astonishing molecular sensitivity

• Dan Lis and
• Francesca Cecchet

Beilstein J. Nanotechnol. 2014, 5, 2275–2292, doi:10.3762/bjnano.5.237

• of biological properties and behaviours, and has opened the way to fascinating biomedical and biotechnological applications of single molecules and nanomaterials [7][17][18][19][20]. This success is mostly due to the electromagnetic near-field enhancement achieved thanks to more and more

• IR or spontaneous Raman spectroscopies. To push forward the performance of both techniques, the coupling of the molecular coherence and power-law intensity dependence with the near-field enhancement from surface plasmon resonance has been initiated, and some demonstrations of an extreme sensitivity

• surface of the nanoparticle [54][55][56][57][58]. Besides, the near-field enhancement has led to a very large variety of advances in many fundamental and applied areas of science. Large boosts in the sensitivity and intensity have been reported for a very wide variety of nanoparticle shapes, dimensions

Nanometer-resolved mechanical properties around GaN crystal surface steps

• Jörg Buchwald,
• Marina Sarmanova,
• Bernd Rauschenbach and
• Stefan G. Mayr

Beilstein J. Nanotechnol. 2014, 5, 2164–2170, doi:10.3762/bjnano.5.225

• element dV at point p arises from the effective stresses acting on the boundaries of its neighboring volumes. Due to the fact that the tensile stresses are homogeneous along {(x,0,z) | 0 ≤ z ≤ h}, the near field behavior of the stress field is a reduction just along its lateral distance y from the step

Properties of plasmonic arrays produced by pulsed-laser nanostructuring of thin Au films

• Katarzyna Grochowska,
• Katarzyna Siuzdak,
• Peter A. Atanasov,
• Carla Bittencourt,
• Anna Dikovska,
• Nikolay N. Nedyalkov and
• Gerard Śliwiński

Beilstein J. Nanotechnol. 2014, 5, 2102–2112, doi:10.3762/bjnano.5.219

• indicate damping confirmed by short dephasing times not exceeding 4 fs, the self-organized Au NP structures reveal quite a strong enhancement of the optical signal. This was consistent with the near-field modeling and micro-Raman measurements as well as a test of the electrochemical sensing capability

• despite the strong damping of the plasmon resonance, the self-organized Au nanostructures reveal sufficient enhancement of the optical signal from the application point of view. Evidence of plasmonic enhancement Near-field effect In the analysis of the electromagnetic field in the vicinity of the particle

• detection based on the refractive index variations [18]. In the particular case of the self-organized NP arrays, such data are crucial for understanding the relation between the structure morphology, the near-field distribution of the optical signal due to the plasmonic resonance effect, the SERS signal

Controlling the optical and structural properties of ZnS–AgInS₂ nanocrystals by using a photo-induced process

• Takashi Yatsui,
• Fumihiro Morigaki and
• Tadashi Kawazoe

Beilstein J. Nanotechnol. 2014, 5, 1767–1773, doi:10.3762/bjnano.5.187

• ], quantum dots (QDs) [4], quantum wells [5], and quantum rings [6]. Kawazoe et al., have demonstrated the room-temperature operation of AND-gate and NOT-gate devices using InAs QD pairs [7]. In a nanophotonic device, near-field energy-transfer via a dipole-forbidden energy state, which is unattainable in

• conventional photonic devices, is used [8]. The near-field energy-transfer originates from an exchange of virtual photons between the resonant energy states [9], where the virtual photons on a nanoparticle activate the dipole-forbidden energy state. The successful fabrication of a nanophotonic device requires

• the control of its size to ensure that the quantized energy levels are resonant to facilitate an efficient optical near-field interaction. The solution process could be a promising process for this purpose because it can easily regulate the size and shape by controlling the growth kinetics [10]. It

Current state of laser synthesis of metal and alloy nanoparticles as ligand-free reference materials for nano-toxicological assays

• Christoph Rehbock,
• Jurij Jakobi,
• Lisa Gamrad,
• Selina van der Meer,
• Daniela Tiedemann,
• Ulrike Taylor,
• Wilfried Kues,
• Detlef Rath and
• Stephan Barcikowski

Beilstein J. Nanotechnol. 2014, 5, 1523–1541, doi:10.3762/bjnano.5.165

• -induced ionization, resulting in highly charged entities which eventually shatter due to charge repulsion [61][62][63]. A third mechanism, postulated for femtosecond pulses at very high fluence, is near-field ablation [64]. However, up to date it is unknown which mechanism prevails under certain

Near-field photochemical and radiation-induced chemical fabrication of nanopatterns of a self-assembled silane monolayer

• Ulrich C. Fischer,
• Carsten Hentschel,
• Florian Fontein,
• Linda Stegemann,
• Christiane Hoeppener,
• Harald Fuchs and
• Stefanie Hoeppener

Beilstein J. Nanotechnol. 2014, 5, 1441–1449, doi:10.3762/bjnano.5.156

• Macromolecular Chemistry (IOMC) and Jena Center for Soft Matter (JCSM), Friedrich Schiller University, Humboldtstr. 10, 07743 Jena, Germany 10.3762/bjnano.5.156 Abstract A general concept for parallel near-field photochemical and radiation-induced chemical processes for the fabrication of nanopatterns of a self

• -assembled monolayer (SAM) of (3-aminopropyl)triethoxysilane (APTES) is explored with three different processes: 1) a near-field photochemical process by photochemical bleaching of a monomolecular layer of dye molecules chemically bound to an APTES SAM, 2) a chemical process induced by oxygen plasma etching

• as well as 3) a combined near-field UV-photochemical and ozone-induced chemical process, which is applied directly to an APTES SAM. All approaches employ a sandwich configuration of the surface-supported SAM, and a lithographic mask in form of gold nanostructures fabricated through colloidal sphere

Observation and analysis of structural changes in fused silica by continuous irradiation with femtosecond laser light having an energy density below the laser-induced damage threshold

• Wataru Nomura,
• Tadashi Kawazoe,
• Takashi Yatsui,
• Makoto Naruse and
• Motoichi Ohtsu

Beilstein J. Nanotechnol. 2014, 5, 1334–1340, doi:10.3762/bjnano.5.146

• performing optical near-field etching on a substrate prepared under the same conditions as sample A. The samples A and B had a minimum average surfaces roughnesses Ra of 0.20 nm and 0.13 nm, respectively [12]. Since we employed a continuous-wave laser with the wavelength of 532 nm and power of 2 W for

• optical near-field etching, the sample B did not have any laser-induced damage or degradation caused by this preparation. Optical near-field etching is a surface planarization technique for selectively removing only minute protrusions in the surface of a substrate, and can flatten the planer substrate

Optical near-fields & nearfield optics

• Alfred J. Meixner and
• Paul Leiderer

Beilstein J. Nanotechnol. 2014, 5, 186–187, doi:10.3762/bjnano.5.19

• -field in the vicinity of nanostructures. In this Thematic Series, various examples for the use of optical near-fields and near-field optics are presented. Metallic nanostructures, especially noble metals such as gold and silver, are efficient for nano-focusing and controlling light on the nanoscale

• , because they support surface plasmons, i.e., collective excitations of the electron gas, which couple strongly to light. As a result, the optical near-field around such plasmonic structures can be enhanced by orders of magnitude compared to the incident light intensity, and can be localized in “hot spots

• ” with a length of a few nanometers. This effect of strong near-field enhancement around sharp structures of noble metals has been known from Surface Enhanced Raman Scattering (SERS) for a long time [1]. Yet, the well-controlled tailoring of nanostructures necessary to quantitatively control the optical