Challenges in realizing ultraflat materials surfaces

• Takashi Yatsui,
• Wataru Nomura,
• Fabrice Stehlin,
• Olivier Soppera,
• Makoto Naruse and
• Motoichi Ohtsu

Beilstein J. Nanotechnol. 2013, 4, 875–885, doi:10.3762/bjnano.4.99

• that utilize the optical near field generated in nanoscale semiconductor quantum structures and the dipole-forbidden near-field energy transfer. Moreover, near-field optics has been used to fabricate nanoscale structures beyond the diffraction limit of light. For example, photolithography has been used

Modulation of defect-mediated energy transfer from ZnO nanoparticles for the photocatalytic degradation of bilirubin

• Tanujjal Bora,
• Karthik K. Lakshman,
• Soumik Sarkar,
• Abhinandan Makhal,
• Samim Sardar,
• Samir K. Pal and
• Joydeep Dutta

Beilstein J. Nanotechnol. 2013, 4, 714–725, doi:10.3762/bjnano.4.81

• of the heme catabolism that can cause jaundice when its excretion is impaired. The photocatalytic degradation of BR activated by ZnO nanoparticles through a non-radiative energy transfer pathway can be influenced by the surface defect-states (mainly the oxygen vacancies) of the catalyst nanoparticles

• . These were modulated by applying a simple annealing in an oxygen-rich atmosphere. The mechanism of the energy transfer process between the ZnO nanoparticles and the BR molecules adsorbed at the surface was studied by using steady-state and picosecond-resolved fluorescence spectroscopy. A correlation of

• photocatalytic degradation and time-correlated single photon counting studies revealed that the defect-engineered ZnO nanoparticles that were obtained through post-annealing treatments led to an efficient decomposition of BR molecules that was enabled by Förster resonance energy transfer. Keywords: bilirubin

Digging gold: keV He⁺ ion interaction with Au

• Vasilisa Veligura,
• Gregor Hlawacek,
• Robin P. Berkelaar,
• Raoul van Gastel,
• Harold J. W. Zandvliet and
• Bene Poelsema

Beilstein J. Nanotechnol. 2013, 4, 453–460, doi:10.3762/bjnano.4.53

• rate is low, it cannot be completely neglected. As He+ ions impinge on the surface at normal incidence, the sputtering of gold atoms by the direct energy transfer from incoming helium is unlikely. Furthermore, the energy transfer from light helium ions to gold atoms in general is limited because of the

Multiple regimes of operation in bimodal AFM: understanding the energy of cantilever eigenmodes

• Daniel Kiracofe,
• Arvind Raman and
• Dalia Yablon

Beilstein J. Nanotechnol. 2013, 4, 385–393, doi:10.3762/bjnano.4.45

• contrast reversal for the elastic case in Figure 7 suggests that the tip–sample energy dissipation plays a key role in the contrast reversal. Presumably, an energy transfer between the eigenmodes is involved. Practically, this result reinforces the suggestion of Stark [18] that energy ratios and not

Near-field effects and energy transfer in hybrid metal-oxide nanostructures

• Ulrich Herr,
• Barat Achinuq,
• Cahit Benel,
• Giorgos Papageorgiou,
• Manuel Goncalves,
• Johannes Boneberg,
• Paul Leiderer,
• Paul Ziemann,
• Peter Marek and
• Horst Hahn

Beilstein J. Nanotechnol. 2013, 4, 306–317, doi:10.3762/bjnano.4.34

• electrical field, which has been utilized in spectroscopy for many years. On the other hand, the excited states in metallic structures decay over very short lifetimes. Longer lifetimes of excited states occur in nonmetallic nanostructures, which makes them attractive for further energy transfer before

• nanoparticles. The oxide particles were doped with rare-earth (RE) ions, which show a large shift between absorption and emission wavelengths, allowing us to investigate the energy-transfer processes in detail. The main focus is on TiO2 nanoparticles doped with Eu3+, since the material is interesting for

• applications such as the generation of hydrogen by photocatalytic splitting of water molecules. We use high-resolution techniques such as confocal fluorescence microscopy for the investigation of energy-transfer processes. The experiments are supported by simulations of the electromagnetic field enhancement in

Nanoscopic surfactant behavior of the porin MspA in aqueous media

• Ayomi S. Perera,
• Hongwang Wang,
• Tej B. Shrestha,
• Deryl L. Troyer and
• Stefan H. Bossmann

Beilstein J. Nanotechnol. 2013, 4, 278–284, doi:10.3762/bjnano.4.30

• of the dynamics of several proteins has been studied by Förster resonance energy transfer (FRET) [15][16][17]. This study was intended to demonstrate the potential of using dynamic light scattering (DLS) and the measurement of zeta potentials when studying the supramolecular aggregation of proteins

Selective surface modification of lithographic silicon oxide nanostructures by organofunctional silanes

• Thomas Baumgärtel,
• Christian von Borczyskowski and
• Harald Graaf

Beilstein J. Nanotechnol. 2013, 4, 218–226, doi:10.3762/bjnano.4.22

• to steric reasons as well as the molecular structure and would also be contradictory to the AFM-investigations. It may also be possible that the fluorescence is quenched by an efficient energy transfer between densely packed FITC molecules on the structure. However, such an effect can be excluded by

Horizontal versus vertical charge and energy transfer in hybrid assemblies of semiconductor nanoparticles

• Gilad Gotesman,
• Rahamim Guliamov and
• Ron Naaman

Beilstein J. Nanotechnol. 2012, 3, 629–636, doi:10.3762/bjnano.3.72

• (NPs) adsorbed on a quartz substrate through organic linkers. Charge and energy transfer processes within the assemblies were investigated as a function of the length of the dithiolated linker (DT) between the donors and acceptors. We found an unusual linker-length-dependency in the emission of the

• donors. This dependency may be explained by charge and energy transfer processes in the vertical direction (from the donors to the acceptors) that depend strongly on charge transfer processes occurring in the horizontal plane (within the monolayer of the acceptor), namely, parallel to the substrate

• . Keywords: charge transfer; energy transfer; nanoparticles; organic linker; quantum dots; Introduction Self-assembled structures of semiconductor nanoparticles (NPs) are viewed as a possible avenue for producing photovoltaic devices with efficient collection of light and charge separation processes [1

Nanolesions induced by heavy ions in human tissues: Experimental and theoretical studies

• Marcus Bleicher,
• Lucas Burigo,
• Marco Durante,
• Maren Herrlitz,
• Michael Krämer,
• Igor Mishustin,
• Iris Müller,
• Francesco Natale,
• Igor Pshenichnov,
• Stefan Schramm,
• Gisela Taucher-Scholz and
• Cathrin Wälzlein

Beilstein J. Nanotechnol. 2012, 3, 556–563, doi:10.3762/bjnano.3.64

• fibroblasts. Cells were irradiated with Au ions (energy: 8 MeV/n, linear energy transfer (LET): 13000 keV/μm; fluence: 3·106 ions/cm2) at a low angle and fixed after 1 h. H4K16ac (green) is increased at damage sites. DNA damage is shown by γH2AX staining (red). DNA is counterstained with ToPro3 (blue). From

Radiation-induced nanostructures: Formation processes and applications

• Michael Huth

Beilstein J. Nanotechnol. 2012, 3, 533–534, doi:10.3762/bjnano.3.61

• in living tissue, which causes different types of DNA damage on bases, as well as single- and double-bond breaks. High-energy particles travel in straight trajectories and have a relatively well-defined stopping point, at which the majority of the energy is deposited. In the tracks, the linear energy

• transfer, i.e., the rate at which ionization is created along the particle trajectory, can amount to more than 100 keV/µm. Proximal tissue, in contrast, only receives radiation by means of the excited secondary electrons whose trajectories are transverse to the particle track. For the electrons in the low

Repulsive bimodal atomic force microscopy on polymers

• Alexander M. Gigler,
• Christian Dietz,
• Maximilian Baumann,
• Nicolás F. Martinez,
• Ricardo García and
• Robert W. Stark

Beilstein J. Nanotechnol. 2012, 3, 456–463, doi:10.3762/bjnano.3.52

• modes are slightly coupled, energy transfer between them can occur [26]. The amplitude of the first eigenmode, indirectly excited through the coupling between the two modes, nearly reaches the initial amplitude of the second eigenmode at the same z-distance before decreasing. No further approach data

Combining nanoscale manipulation with macroscale relocation of single quantum dots

• Francesca Paola Quacquarelli,
• Richard A. J. Woolley,
• Martin Humphry,
• Jasbiner Chauhan,
• Philip J. Moriarty and
• Ashley Cadby

Beilstein J. Nanotechnol. 2012, 3, 324–328, doi:10.3762/bjnano.3.36

• operator. As the colour of a QD is size-dependent, the manipulation algorithm could be used with dual-colour samples in order to build up structures in which energy transfer is utilized. Conclusion We have shown that it is possible to isolate and manipulate individual CdSe quantum dots on a sapphire

Nonconservative current-induced forces: A physical interpretation

• Tchavdar N. Todorov,
• Daniel Dundas,
• Anthony T. Paxton and
• Andrew P. Horsfield

Beilstein J. Nanotechnol. 2011, 2, 727–733, doi:10.3762/bjnano.2.79

• energy transfer from electrical current into atomic motion are only just starting to be explored. Two aspects of the effect that are of immediate interest are its capacity to drive an atomic-scale motor, and its possible potent role as a cause for dramatic mechanical failure [12][13][14]. Indeed, the

Optical properties of fully conjugated cyclo[n]thiophenes – An experimental and theoretical approach

• Elena Mena-Osteritz,
• Fan Zhang,
• Günther Götz,
• Peter Reineker and
• Peter Bäuerle

Beilstein J. Nanotechnol. 2011, 2, 720–726, doi:10.3762/bjnano.2.78

• can be attributed to the emission from the second excited state, S2 (Figure 1, Table 1 and Figure 3). This double fluorescence behavior becomes possible because an incomplete energy transfer to the S1 state occurs allowing partially the emission from the populated higher excited state S2. In a

Distance dependence of near-field fluorescence enhancement and quenching of single quantum dots

• Volker Walhorn,
• Jan Paskarbeit,
• Heinrich Gotthard Frey,
• Alexander Harder and
• Dario Anselmetti

Beilstein J. Nanotechnol. 2011, 2, 645–652, doi:10.3762/bjnano.2.68

• spectroscopy, energy transfer processes between single fluorophores and fluorophore quencher pairs play an important role in the investigation of molecular distances or orientations. At distances larger than about 3 nm these effects originate predominantly from dipolar coupling. As these experiments are

• experimental data. Moreover, we revealed and quantified the influence of interfering processes such as field enhancement confined at interface boundaries, mirror dipoles and (resonant) dipolar coupling. Keywords: AFM; fluorescence energy transfer; multiple multipole simulation; quantum dots; Introduction

• fluorescence resonance energy transfer (FRET) [1] between individual molecules, open up fascinating means to explore inter- or intramolecular distances [2], orientation [3], affinity and binding dynamics at the single-molecule level [4]. The combination of fluorescence with single-molecule manipulation

Room temperature excitation spectroscopy of single quantum dots

• Christian Blum,
• Frank Schleifenbaum,
• Martijn Stopel,
• Sébastien Peter,
• Marcus Sackrow,
• Vinod Subramaniam and
• Alfred J. Meixner

Beilstein J. Nanotechnol. 2011, 2, 516–524, doi:10.3762/bjnano.2.56

• such as Förster resonance energy transfer (FRET) pairs, fluorescent proteins and upconversion particles. Experimental We realized an instrument capable of single molecule excitation spectroscopy by combining a high power supercontinuum white light source (Fianium SC-400pp) with a grating spectrometer

Towards a scalable and accurate quantum approach for describing vibrations of molecule–metal interfaces

• David M. Benoit,
• Bruno Madebene,
• Inga Ulusoy,
• Luis Mancera,
• Yohann Scribano and
• Sergey Chulkov

Beilstein J. Nanotechnol. 2011, 2, 427–447, doi:10.3762/bjnano.2.48

• freedom. These coupling terms typically contribute significantly less than the 1-D terms but have important implications for vibrational resonances and energy transfer. The 3-D and higher terms add smaller corrections to the PES that are only required for a very high accuracy description. Note that the

Characterization of protein adsorption onto FePt nanoparticles using dual-focus fluorescence correlation spectroscopy

• Pauline Maffre,
• Karin Nienhaus,
• Faheem Amin,
• Wolfgang J. Parak and
• G. Ulrich Nienhaus

Beilstein J. Nanotechnol. 2011, 2, 374–383, doi:10.3762/bjnano.2.43

• mutual interactions, the C-terminal domain is kept in close proximity to the N-terminal helix bundle, contributing significantly to the stability of the lipid-free conformation [39]. Förster resonance energy transfer (FRET) studies have indicated that the inter-domain distance in solution is even smaller

Fabrication and spectroscopic studies on highly luminescent CdSe/CdS nanorod polymer composites

• Jana Bomm,
• Andreas Büchtemann,
• Angela Fiore,
• Liberato Manna,
• James H. Nelson,
• Diana Hill and
• Wilfried G. J. H. M. van Sark

Beilstein J. Nanotechnol. 2010, 1, 94–100, doi:10.3762/bjnano.1.11

• , aggregation of nanoparticles, loss of transparency and luminescence quenching due to exciton energy transfer [2][7]. Several methods have been described to overcome these problems for quantum dot polymer composites. For example, Bawendi and coworkers incorporated trioctylphosphine oxide covered CdSe/ZnS QDs