Andrey A Lutich

Ludwig-Maximilian-University of Munich, München, Bavaria, Germany

Are you Andrey A Lutich?

Claim your profile

Publications (40)238.44 Total impact

  • [Show abstract] [Hide abstract]
    ABSTRACT: This feature article discusses the optical trapping and manipulation of plasmonic nanoparticles, an area of current interest with potential applications in nanofabrication, sensing, analytics, biology and medicine. We give an overview over the basic theoretical concepts relating to optical forces, plasmon resonances and plasmonic heating. We discuss fundamental studies of plasmonic particles in optical traps and the temperature profiles around them. We place a particular emphasis on our own work employing optically trapped plasmonic nanoparticles towards nanofabrication, manipulation of biomimetic objects and sensing.
    Nanoscale 03/2014; · 6.73 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Following the long dominance of CdSe quantum dots as the paradigm semiconductor nanocrystals for investigating of strong quantum confinement phenomena, attention is paid to the lead chalcogenide quantum dots which possess a level of carrier confinement unachievable in quantum dots of other materials. However, the energy level structure of the lowest 1S–1S exciton in these quantum dots is not defined well. Here, we report on the experimental investigation of absorption and photoluminescence of PbS quantum dots with a mean radius of 2.4 nm and show that the 1S–1S absorption and photoluminescence band maxima obey different temperature dependences. The temperature decrease leads to the increase of the Stokes shift. The results are in qualitative agreement with the assumption that different inherent exciton states within the split 1S–1S exciton state are responsible for the absorption and emission of light by PbS quantum dots.
    Physica E Low-dimensional Systems and Nanostructures 09/2013; 53:63–65. · 1.52 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: We report on the tuning of specific binding of DNA attached to gold nanoparticles at the individual particle pair (dimer) level in an optical trap by means of plasmonic heating. DNA hybridization events are detected optically by the change in the plasmon resonance frequency due to plasmonic coupling of the nanoparticles. We find that at larger trapping powers (i.e. larger temperatures and stiffer traps) the hybridization rates decrease by more than an order of magnitude. This result is explained by higher temperatures preventing the formation of dimers with lower binding energies. Our results demonstrate that plasmonic heating can be used to fine-tune the binding kinetics of biomolecular binding events.
    Nano Letters 06/2013; · 13.03 Impact Factor
  • Advanced Optical Materials. 02/2013; 1(2).
  • [Show abstract] [Hide abstract]
    ABSTRACT: We present results of a comparative study of colloidal anatase titanium oxide nanorods and extremely thin atomic wires of systematically decreasing (2.6 nm down to 0.5 nm) diameter in terms of their optical absorption as well as steady-state and time-resolved photoluminescence. Steady-state photoluminescence spectra of the titania samples show three well-distinguished spectral components, which are ascribed to excitonic emission (4.26 ± 0.2 eV), as well as radiative recombination of trapped holes with electrons from the conduction band (4.04 ± 0.4 eV) and radiative recombination of trapped electrons with holes in the valence band (3.50 ± 0.2 eV) in nanocrystalline anatase TiO(2). Time-resolved photoluminescence measurements point out the existence of different emissive species responsible for the appearance of high-energetic and low-energetic emission peaks of TiO(2) atomic wires and nanorods.
    Nanoscale 01/2013; · 6.73 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Surface-chemistry of individual, optically trapped plasmonic nanoparticles is modified and accelerated by plasmonic overheating. Depending on the optical trapping power, gold nanorods can exhibit red shifts of their plasmon resonance (i.e., increasing aspect ratio) under oxidative conditions. In contrast, in bulk exclusively blue shifts (decreasing aspect ratios) are observed. Supported by calculations, we explain this finding by local temperatures in the trap exceeding the boiling point of the solvent that cannot be achieved in bulk.
    Nano Letters 08/2012; 12(9):4647-50. · 13.03 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Designing nanoscale objects with the potential to perform externally controlled motion in biological environments is one of the most sought-after objectives in nanotechnology. Different types of chemically and physically powered motors have been prepared at the macro- and microscale. However, the preparation of nanoscale objects with a complex morphology, and the potential for light-driven motion has remained elusive to date. Here, we go a step forward by designing a nanoscale hybrid with a propeller-resembling shape, which can be controlled by focused light under biological conditions. Our hybrid, hereafter "Au@DNA-origami", consists of a spherical gold nanoparticle with self-assembled, biocompatible, two-dimensional (2D) DNA sheets on its surface. As a first step toward the potential utilization of these nanoscale objects as light-driven assemblies in biological environments, we show that they can be optically trapped, and hence translated and deposited on-demand, and that under realistic trapping conditions the thermally induced dehybridization of the DNA sheets can be avoided.
    Nano Letters 08/2012; 12(9):5008-13. · 13.03 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: We report on ‘optical force stamping’ lithography [1], a new approach that employs optical forces on single nanoparticles and allows for parallel nanoparticle printing with precision at least 5x better than the diffraction limit
    05/2012;
  • [Show abstract] [Hide abstract]
    ABSTRACT: To investigate whether multispectral optoacoustic tomography (MSOT) can reveal the heterogeneous distributions of exogenous agents of interest and vascular characteristics through tumors of several millimeters in diameter in vivo. Procedures involving animals were approved by the government of Upper Bavaria. Imaging of subcutaneous tumors in mice was performed by using an experimental MSOT setup that produces transverse images at 10 frames per second with an in-plane resolution of approximately 150 μm. To study dynamic contrast enhancement, three mice with 4T1 tumors were imaged before and immediately, 20 minutes, 4 hours, and 24 hours after systemic injection of indocyanine green (ICG). Epifluorescence imaging was used for comparison. MSOT of a targeted fluorescent agent (6 hours after injection) and hemoglobin oxygenation was performed simultaneously (4T1 tumors: n = 3). Epifluorescence of cryosections served as validation. The accumulation owing to enhanced permeability and retention in tumors (4T1 tumors: n = 4, HT29 tumors: n = 3, A2780 tumors: n = 2) was evaluated with use of long-circulating gold nanorods (before and immediately, 1 hour, 5 hours, and 24 hours after injection). Dark-field microscopy was used for validation. Dynamic contrast enhancement with ICG was possible. MSOT, in contrast to epifluorescence imaging, showed a heterogeneous intratumoral agent distribution. Simultaneous imaging of a targeted fluorescent agent and oxy- and deoxyhemoglobin gave functional information about tumor vasculature in addition to the related agent uptake. The accumulation of gold nanorods in tumors seen at MSOT over time also showed heterogeneous uptake. MSOT enables live high-spatial-resolution observations through tumors, producing images of distributions of fluorochromes and nanoparticles as well as tumor vasculature.
    Radiology 05/2012; 263(2):461-8. · 6.34 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: We explore a new application of optical tweezers for ultrasensitive detection of sound waves in liquid media. Position tracking of a single gold nanoparticle confined in a three-dimensional optical trap is used to readout acoustic vibrations at a sound power level down to -60  dB, causing a ∼90  μeV increase in kinetic energy of the nanoparticle. The unprecedented sensitivity of such a nanoear is achieved by processing the nanoparticle's motion in the frequency domain. The concept developed here will enable us to access the interior of biological microorganisms and micromechanical machines not accessible by other microscopy types.
    Physical Review Letters 01/2012; 108(1):018101. · 7.73 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Microfluidic jetting is a promising method to produce giant unilamellar phospholipid vesicles for mimicking living cells in biomedical studies. We have investigated the chemical composition of membranes of vesicles prepared using this approach by means of Raman scattering spectroscopy. The membranes of all jetted vesicles are found to contain residuals of the organic solvent decane used in the preparation of the initial planar membrane. The decane inclusions are randomly distributed over the vesicle surface area and vary in thickness from a few to several tens of nanometers. Our findings point out that the membrane properties of jetted vesicles may differ considerably from those of vesicles prepared by other methods and from those of living cells.
    Journal of Biophotonics 01/2012; 5(1):40-6. · 3.86 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Here we introduce a new paradigm of far-field optical lithography, optical force stamping lithography. The approach employs optical forces exerted by a spatially modulated light field on colloidal nanoparticles to rapidly stamp large arbitrary patterns comprised of single nanoparticles onto a substrate with a single-nanoparticle positioning accuracy well beyond the diffraction limit. Because the process is all-optical, the stamping pattern can be changed almost instantly and there is no constraint on the type of nanoparticle or substrates used.
    Nano Letters 11/2011; 11(11):5066-70. · 13.03 Impact Factor
  • Michael Fedoruk, Andrey A Lutich, Jochen Feldmann
    [Show abstract] [Hide abstract]
    ABSTRACT: We propose and demonstrate a hybrid lithographic technique capable of nanopatterning surfaces by optothermal decomposition of a polymeric film induced by a single metal nanoparticle. A tightly focused laser beam exerting a strong optical force onto the nanoparticle is used to move it inside the polymer film. Due to efficient plasmonic absorption of the laser light, the nanoparticle is heated up to temperatures of several hundred degrees, causing melting or even thermal decomposition of the polymer film. By this method, grooves less than 100 nm wide and tens of micrometers long can be directly milled in a polymer layer.
    ACS Nano 08/2011; 5(9):7377-82. · 12.03 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Hybrid structures of colloidal quantum dots (QDs) with Ru-dyes have been studied as candidates for panchromatic sensitizers for TiO2-based solar cells. Steady-state and time resolved photoluminescence spectroscopy and photocurrent measurements have been employed to identify the prevailing transfer mechanisms for photogenerated excitons between CdSe QDs capped with a traditional bulky organic ligand trioctylphosphine and Ru-dyes (N3 or Ru505) deposited onto inert glass or mesoporous TiO2 substrates. The type II energy level alignment between the QDs and both N3 and Ru505 offers a possibility for the directional charge separation, with electrons transferred to the QDs and holes to the dye. This scenario is indeed valid for the QD/Ru505 and TiO2/QD/Ru505 hybrid systems, with the negligible spectral overlap between the emission of the QDs and the absorption of the Ru505 dye. For the QD/N3 and TiO2/QD/N3 hybrid systems, the spectral overlap favors the longer range energy transfer from the QDs to N3, independently of the presence of the electron acceptor TiO2.
    Journal of Applied Physics 07/2011; 110(1):014314-014314-7. · 2.21 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: We have coated gold nanorods (NRs) with thermoresponsive microgel shells based on poly(N-isopropylacrylamide) (pNIPAM). We demonstrate by simultaneous laser-heating and optical extinction measurements that the Au NR cores can be simultaneously used as fast optothermal manipulators (switchers) and sensitive optical reporters of the microgel state in a fully externally controlled and reversible manner. We support our results with optical modeling based on the boundary element method and 3D numerical analysis on the temperature distribution. Briefly, we show that due to the sharp increase in refractive index resulting from the optothermally triggered microgel collapse, the longitudinal plasmon band of the coated Au NRs is significantly red-shifted. The optothermal control over the pNIPAM shell, and thereby over the optical response of the nanocomposite, is fully reversible and can be simply controlled by switching on and off a NIR heating laser. In contrast to bulk solution heating, we demonstrate that light-triggering does not compromise colloidal stability, which is of primary importance for the ultimate utilization of these types of nanocomposites as remotely controlled optomechanical actuators, for applications spanning from drug delivery to photonic crystals and nanoscale motion.
    Nanotechnology 06/2011; 22(24):245708. · 3.84 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: We propose and demonstrate a new method of an all-optical, contactless, one-step injection of single gold nanoparticles through phospholipid membranes. The method is based on the combination of strong optical forces acting on and simultaneous optical heating of a gold nanoparticle exposed to laser light tuned to the plasmon resonance of the nanoparticle. A focused laser beam captures single nanoparticles from the colloidal suspension, guides them toward a phospholipid vesicle and propels them through the gel-phase membrane, resulting in the nanoparticle internalization into the vesicle. Efficient resonant optical heating of the gold nanoparticle causes a pore to form in the gel-phase membrane, a few-hundred nanometers in size, which remains open for several minutes.
    ACS Nano 05/2011; 5(5):3585-90. · 12.03 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: We report on tuning the light absorption properties of Cu1.97S nanocrystals upon organization in ordered supercrystal structures. In particular, we show that the weak absorption profile of Cu1.97S nanocrystals can be tuned toward the red part of the visible spectrum. We demonstrate that the controlled addition of ligands to the supercrystals can be used to trigger nanocrystal deassembly, leading to the recovery of the optical properties of the isolated nanocrystals and thus, to a lower absorption in the red part of the spectrum. Supported by structural characterization via electron microscopy and X-ray diffraction our results suggest that the tuning is primarily a consequence of nanocrystal close-packing. Our results highlight an effective approach for extending the light absorption characteristics of Cu1.97S nanocrystals toward the visible that may be relevant for their application in nanocrystal-based photovoltaics.Keywords: nanocrystals; copper sulfide; supercrystals; assembly; absorption; light-harvesting
    Chemistry of Materials. 03/2011; 23(7).
  • [Show abstract] [Hide abstract]
    ABSTRACT: We demonstrate that optical trapping of multiple silver nanoparticles is strongly influenced by plasmonic coupling of the nanoparticles. Employing dark-field Rayleigh scattering imaging and spectroscopy on multiple silver nanoparticles optically trapped in three dimensions, we experimentally investigate the time-evolution of the coupled plasmon resonance and its influence on the trapping stability. With time the coupling strengthens, which is observed as a gradual red shift of the coupled plasmon scattering. When the coupled plasmon becomes resonant with the trapping laser wavelength, the trap is destabilized and nanoparticles are released from the trap. Modeling of the trapping potential and its comparison to the plasmonic heating efficiency at various nanoparticle separation distances suggests a thermal mechanism of the trap destabilization. Our findings provide insight into the specificity of three-dimensional optical manipulation of plasmonic nanostructures suitable for field enhancement, for example for surface-enhanced Raman scattering.
    Nano Letters 03/2011; 11(4):1770-4. · 13.03 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: We report a facile grafting-from strategy towards the synthesis of inorganic–organic composites of semiconductor nanocrystals and wide-bandgap polymers. Amino-functional fluorenes have been used as co-ligands for CdSenanocrystals, thus enabling us to design their surface directly during the synthesis. Highly monodisperse, strongly emitting CdSenanocrystals have been obtained. Subsequently, a straightforward Yamamoto C–C coupling protocol was used to carry out surface polymerisation, hence modifying CdSenanocrystals with oligo- and poly(fluorene) moieties. Both amino-fluorene capped CdSenanocrystals and the resulting nanocrystal–polymer composites were characterized in detail by optical and FT-IR spectroscopy, TEM, AFM, and gel permeation chromatography, showing their potential as novel functional inorganic–organic hybrid materials.
    Journal of Materials Chemistry 02/2011; 21(8):2656-2662. · 5.97 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: We show that well-defined plasmonic nanoresonator made of two gold nanoparticles, separated by less than the particle radius, can be used to significantly accelerate fluorescence energy transfer (FRET). While ensembles of nanoresonators with multiple FRET systems attached exhibit FRET acceleration similar to isolated gold nanoparticles, model calculations reveal different, spatially non-uniform rate enhancement distributions around individual nanostructures with both regions of FRET rate enhancement and suppression. This underlines the importance of precise positional control of both donor and acceptor with respect to the nanoresonator to make full use of its potential for FRET acceleration.
    Chemical Physics Letters 01/2011; 508(1):67-70. · 2.15 Impact Factor

Publication Stats

254 Citations
238.44 Total Impact Points

Institutions

  • 2009–2014
    • Ludwig-Maximilian-University of Munich
      • Photonics and Optoelectronics Group
      München, Bavaria, Germany
    • Universitat Jaume I
      • Departament de Física
      Castelló de la Plana, Valencia, Spain
  • 2013
    • City University of Hong Kong
      Chiu-lung, Kowloon City, Hong Kong
  • 2008–2009
    • National Academy of Sciences of Belarus
      • B.I.Stepanov Institute of Physics
      Myenyesk, Minsk, Belarus