@article{HullGrayKammleretal., author = {Hull, Robert and Gray, J. L. and Kammler, Martin and Vandervelde, T. and Kobayashi, Takeshi and Kumar, P. and Pernell, T. and Bean, J. C. and Floro, J. A. and Ross, Frances M.}, title = {Precision placement of heteroepitaxial semiconductor quantum dots}, series = {Materials Science and Engineering: B}, volume = {101}, journal = {Materials Science and Engineering: B}, number = {1-3}, publisher = {Elsevier}, doi = {10.1016/S0921-5107(02)00680-3}, pages = {1 -- 8}, abstract = {We describe two new approaches to the patterning of Si(1 0 0) surfaces for controlled nucleation of heteroepitaxial Ge semiconductor clusters. In the first method, a Ga ' -focused ion beam in situ to the growth chamber is used to create local regions of enhanced Ga ' concentration and surface topography. It is shown that at low ion doses ({\^A}/10 14 cm (2), implanted Ga causes local nucleation of Ge clusters upon the implanted region. At higher doses (]/10 15 cm (2), a complex surface topography localizes nucleation of Ge clusters. This approach can be used to seed complex patterns of Ge clusters with diameters of tens of nanometers and positional accuracy of sub-100 nm. The second method employs self-assembly of complex strain-stabilized ''quantum quadruplet'' and ''quantum fortress'' structures, whereby cooperative island nucleation around shallow strain-relieving pits is identified during Ge x Si 1(x /Si(1 0 0) heteroepitaxy. These configurations are kinetically limited structures that exist over a range of compositions, growth temperatures, and growth rates, but which are destabilized by strain relaxation (e.g. by the introduction of misfit dislocations) and by growth conditions which provide high adatom surface mobilities. Both methods have broad potential application to nanoelectronic device architectures. 2003 Elsevier Science B.V. All rights reserved.}, language = {en} } @article{HanischBlicharskiJanzenKrenzeretal., author = {Hanisch-Blicharski, Anja and Janzen, Andreas and Krenzer, Boris and Wall, S. and Klasing, Friedrich and Kalus, Annika and Frigge, Tim and Kammler, Martin and Horn-von Hoegen, Michael}, title = {Ultra-fast electron diffraction at surfaces: from nanoscale heat transport to driven phase transitions}, series = {Ultramicroscopy}, volume = {127}, journal = {Ultramicroscopy}, publisher = {Elsevier}, doi = {10.1016/j.ultramic.2012.07.017}, pages = {2 -- 8}, abstract = {Many fundamental processes of structural changes at surfaces occur on a pico- or femtosecond time scale. In order to study such ultra-fast processes, we have combined modern surface science techniques with fs-laser pulses in a pump-probe scheme. Reflection high energy electron diffraction (RHEED) with grazing incident electrons ensures surface sensitivity for the probing electron pulses. Utilizing the Debye-Waller effect, we studied the cooling of vibrational excitations in monolayer adsorbate systems or the nanoscale heat transport from an ultra-thin film through a hetero-interface on the lower ps-time scale. The relaxation dynamics of a driven phase transition far away from thermal equilibrium is demonstrated with the In-induced (8×2) reconstruction on Si(111). This surface exhibits a Peierls-like phase transition at 100K from a (8×2) ground state to (4×1) excited state. Upon excitation by a fs-laser pulse, this structural phase transition is driven into an excited (4×1) state at a sample temperature of 20K. Relaxation into the (8×2) ground state occurs after more than 150 ps.}, language = {en} } @article{MenzelKammlerConradetal., author = {Menzel, Andreas and Kammler, Martin and Conrad, E. H. and Yeh, V. and Hupalo, Myron and Tringides, Michael C.}, title = {Kinetics measurements of Pb island growth on Si(111)}, series = {Physical Review B}, volume = {67}, journal = {Physical Review B}, number = {16}, publisher = {American Physical Society}, doi = {10.1103/PhysRevB.67.165314}, abstract = {We present the results of kinetics experiments on quantum-size-effects (QSE) Pb islands formed on Si(111). We have looked at the evolution of seven-layer Pb islands from five-layer Pb islands due to the transport of Pb atoms from the interisland region, overcoming a barrier at the island edges, and moving to the island tops. By analyzing low-energy electron-diffraction and scanning-tunneling microscopy data, we have estimated the barrier for layer formation in this system to be ∼0.32eV. This energy is much larger than that expected from QSE electronic contributions alone.}, language = {en} } @inproceedings{KammlerHornvonHoegenVossetal., author = {Kammler, Martin and Horn- von Hoegen, Michael and Voss, N. and Tringides, Michael C. and Menzel, Andreas and Conrad, E. H.}, title = {Surface Dynamics of Stepped Si(001) Studied by Temporal Leed Spectroscopy}, series = {Collective Diffusion on Surfaces: Correlation Effects and Adatom Interactions (NATO Science Series II: Mathematics, Physics and Chemistry}, volume = {29}, booktitle = {Collective Diffusion on Surfaces: Correlation Effects and Adatom Interactions (NATO Science Series II: Mathematics, Physics and Chemistry}, publisher = {Springer}, doi = {10.1007/978-94-010-0816-7_3}, pages = {23 -- 32}, abstract = {We present the first demonstration of Temporal LEED Spectroscopy's ability to measure surface dynamics as shown by a study of step dynamics on vicinal Si(001). While we measure activation energies consistent with other work, the observed microscopic mechanism driving the fluctuations is inconsistent with previous claims. We exclude evaporation/condensation of atoms from the steps as the rate limiting kinetics in the temperature range of this experiment. Possible reasons for these differences are discussed.}, language = {en} } @article{StreubuehrKalusZhouetal., author = {Streub{\"u}hr, C. and Kalus, Annika and Zhou, Ping and Ligges, Manuel and Hanisch-Blicharski, Anja and Kammler, Martin and Bovensiepen, U. and Horn-von Hoegen, Michael and von der Linde, D.}, title = {Comparing ultrafast surface and bulk heating using time-resolved electron diffraction}, series = {Applied Physics Letters}, volume = {104}, journal = {Applied Physics Letters}, publisher = {American Institute of Physics}, doi = {10.1063/1.4872055}, pages = {1 -- 3}, abstract = {From measurements of the transient Debye-Waller effect in Bismuth, we determine the buildup time of the random atomic motion resulting from the electronic relaxation after short pulse laser excitation. The surface sensitive reflection high energy electron diffraction and transmission electron diffraction yield a time constant of about 12 ps and 3 ps, respectively. The different energy transfer rates indicate relatively weak coupling between bulk and surface vibrational modes. (C) 2014 AIP Publishing LLC.}, language = {en} } @inproceedings{ShymanovichNicoulLuetal., author = {Shymanovich, Uladzimir and Nicoul, Matthieu and Lu, Wei and Tarasevitch, A. and Kammler, Martin and Horn-von Hoegen, Michael and von der Linde, D. and Sokolowski-Tinten, Klaus and Phipps, Claude}, title = {Coherent acoustic and optical phonons in laser-excited solids studied by ultrafast time-resolved X-ray diffraction}, series = {AIP Conference Proceedings}, booktitle = {AIP Conference Proceedings}, number = {1}, publisher = {AIP}, doi = {10.1063/1.3507146}, pages = {558 -- 566}, abstract = {We apply ultrafast time-resolved X-ray diffraction to directly study coherent acoustic and optical phonons in laser-excited materials. In Au the ps acoustic response has been investigated with the particular goal to clarify the interplay of electronic and thermal pressure contributions. In Bi the extreme softening of the coherently excited A 1 g optical phonon presents strong indication that upon intense laser-excitation the Peierls-transition which determines the equilibrium structure of Bi can be reversed. In FeRh we studied the lattice response after a fast laser-induced anti-ferromagnetic to ferromagnetic phase transition.}, language = {en} } @article{PayerKleinAcetetal., author = {Payer, Thomas and Klein, C. and Acet, M. and Ney, V. and Kammler, Martin and Meyer zu Heringdorf, Frank-Joachim and Horn-von Hoegen, Michael}, title = {High-quality epitaxial Bi(111) films on Si(111) by isochronal annealing}, series = {Thin Solid Films}, volume = {520}, journal = {Thin Solid Films}, number = {23}, publisher = {Elsevier}, doi = {10.1016/j.tsf.2012.06.004}, pages = {6905 -- 6908}, abstract = {Bi(111) films grown on Si(111) at room temperature show a significantly higher roughness compared to Bi films grown on Si(100) utilizing a kinetic pathway based on a low-temperature process. Isochronal annealing steps of 3 min duration each with temperatures up to 200 °C cause a relaxation of the Bi films' lattice parameter toward the Bi bulk value and yield an atomically flat Bi surface. Driving force for the relaxation and surface reordering is the magic mismatch of 11 Bi atoms to 13 Si atoms that emerges at annealing temperatures above 150 °C and reduces the remaining strain to less than 0.2\%.}, language = {en} } @inproceedings{ZhouStreubuehrKalusetal., author = {Zhou, Ping and Streub{\"u}hr, C. and Kalus, Annika and Frigge, Tim and Wall, S. and Hanisch-Blicharski, Anja and Kammler, Martin and Ligges, Manuel and Bovensiepen, U. and von der Linde, D. and Horn-von Hoegen, Michael}, title = {Ultrafast time resolved reflection high energy electron diffraction with tilted pump pulse fronts}, series = {EPJ Web of Conferences - XVIIIth International Conference on Ultrafast Phenomena}, volume = {41}, booktitle = {EPJ Web of Conferences - XVIIIth International Conference on Ultrafast Phenomena}, publisher = {EPJ}, doi = {10.1051/epjconf/20134110016}, abstract = {We present time-resolved RHEED from a laser excited Pb(111) surface using a pulse front tilter for the compensation of the velocity mismatch of electrons and light. The laser pulses with tilted fronts were characterized by a spatially resolving cross correlator. The response of the surface upon excitation was observed to be less than 2 ps.}, language = {en} } @inproceedings{LuNicoulShymanovichetal., author = {Lu, Wei and Nicoul, Matthieu and Shymanovich, Uladzimir and Tarasevitch, A. and Kammler, Martin and Horn-von Hoegen, Michael and von der Linde, D. and Sokolowski-Tinten, Klaus}, title = {Transient reversal of a Peierls-transition: Extreme phonon softening in laser-excited Bismuth}, series = {International Conference on Ultrafast Phenomena, Snowmass}, booktitle = {International Conference on Ultrafast Phenomena, Snowmass}, number = {ME41}, publisher = {Optica Publishing Group}, doi = {10.1364/UP.2010.ME41}, abstract = {Laser-excited coherent optical phonons in Bismuth were investigated using time-resolved X-ray diffraction. The observed extreme softening of the excited A1g-mode presents strong indication that the Peierls-distortion defining the equilibrium structure of Bismuth is transiently reversed.}, language = {en} } @article{PortavoceKammlerHulletal., author = {Portavoce, A. and Kammler, Martin and Hull, Robert and Reuter, Mark C. and Copel, M. and Ross, Frances M.}, title = {Growth of nanostructures by locally modified surface reactivity}, series = {Materials Science in Semiconductor Processing}, volume = {12}, journal = {Materials Science in Semiconductor Processing}, number = {1-2}, publisher = {Elsevier}, doi = {10.1016/j.mssp.2009.07.001}, pages = {25 -- 30}, abstract = {The chemical vapor deposition (CVD) of Si and Ge on Si(0 0 1) substrates covered by 1 monolayer of Ga has been studied. Ga modifies surface reactivity and surface atom mobility. We show that islanding occurs during Ga-mediated CVD even in the absence of strain, allowing for the formation of islands without a wetting layer or with a thinner wetting layer. The morphology of the grown layer is highly dependent on kinetic parameters, i.e. growth temperature and growth pressure, that control Si and Ge deposition and Ga desorption. Si Ga-mediated CVD promotes the formation of self-assembled epitaxial Si islands exhibiting {1 1 3} facets. Ge islands grown by Ga-mediated CVD present reduced lateral sizes and an increased surface density compared to non Ga-mediated CVD. The growth morphology (particularly island size and density) can be understood by considering a qualitative model in which atoms are deposited only on sites whose dangling bonds are not passivated by Ga. We suggest that modification of surface reactivity during surfactant-mediated CVD can thus provide a new degree of freedom for quantum dot fabrication.}, language = {en} } @article{PortavoceKammlerHulletal., author = {Portavoce, A. and Kammler, Martin and Hull, Robert and Reuter, Mark C. and Ross, Frances M.}, title = {Mechanism of the nanoscale localization of Ge quantum dot nucleation on focused ion beam templated Si(001) surfaces}, series = {Nanotechnology}, volume = {17}, journal = {Nanotechnology}, number = {17}, publisher = {IOP}, doi = {10.1088/0957-4484/17/17/028}, pages = {4451 -- 4455}, abstract = {We investigate the fundamental mechanism by which self-assembled Ge islands can be nucleated at specific sites on Si(001) using ultra-low-dose focused ion beam (FIB) pre-patterning. Island nucleation is controlled by a nanotopography that forms after the implantation of Ga ions during subsequent thermal annealing of the substrate. This nanotopography evolves during the annealing stage, changing from a nanoscale annular depression associated with each focused ion beam spot to a nanoscale pit, and eventually disappearing (planarizing). The correspondence of Ge quantum dot nucleation sites to the focused ion beam features requires a growth surface upon which the nanotopography is preserved. A further key observation is that the Ge wetting layer thickness is reduced in patterned regions, allowing the formation of islands on the templated regions without nucleation elsewhere. These results provide routes to the greatly enhanced design and control of quantum dot distributions and dimensions.}, language = {en} } @article{RossKammlerReuteretal., author = {Ross, Frances M. and Kammler, Martin and Reuter, Mark C. and Hull, Robert}, title = {In-situ observations of self-assembled island nucleation on patterned substrates}, series = {Philosophical Magazine}, volume = {84}, journal = {Philosophical Magazine}, number = {25-26}, publisher = {Taylor \& Francis}, doi = {10.1080/14786430410001671430}, pages = {2687 -- 2702}, abstract = {We compare in-situ electron microscopy observations of Ge island growth on Si surfaces modulated by different techniques. Si(001) substrates were patterned either using a focused Ga ion beam or lithographically to produce similar feature sizes. In the case of the focused-ion-beam patterned substrates, chemical or strain effects caused by low Ga doses control the positions at which islands nucleate. Nucleation on topographically modulated substrates, with the pattern produced either by high-dose sputtering or lithographically, is controlled by the nature of the side walls of topographic features. The two patterning approaches have different benefits in creating arrays of islands for device applications.}, language = {en} } @article{MenzelConradTringidesetal., author = {Menzel, Andreas and Conrad, E. H. and Tringides, Michael C. and Kammler, Martin and Horn- von Hoegen, Michael}, title = {Finite collection time effects in autocovariance function measurements}, series = {Journal of Applied Physics}, volume = {93}, journal = {Journal of Applied Physics}, number = {4}, publisher = {AIP Publishing}, doi = {10.1063/1.1537466}, pages = {2229 -- 2235}, abstract = {In this paper we discuss how finite data sets influence experimental measurements of the autocovariance function. Autocovariance estimators are biased, meaning that the expectation value for any measured autocovariance function is not identical to the actual autocovariance function. In this work we show that the measured autocovariance function for a finite length time series must become negative for some lag times. We derive analytic corrections to these finite time errors for different types of correlated random sequences. Our results explain the apparent anticorrelated noise observed in experimental observations.}, language = {en} } @article{KammlerHullReuteretal., author = {Kammler, Martin and Hull, Robert and Reuter, Mark C. and Ross, Frances M.}, title = {Lateral control of self-assembled island nucleation by focused-ion-beam micropatterning}, series = {Applied Physics Letters}, volume = {82}, journal = {Applied Physics Letters}, number = {7}, doi = {10.1063/1.1542680}, pages = {1093 -- 1095}, abstract = {We demonstrate that the nucleation sites of nanoscale, self-assembled Ge islands on Si(001) can be controlled by patterning the Si surface in situ with a focused ion beam. At low doses of 6000 Ga+ ions per <100 nm spot, the selective growth is achieved without modifying the initial surface topography. At larger doses, topographic effects produced by sputtering and redeposition control the selective nucleation sites. Islands grown on irradiated spots are smaller with higher aspect ratio than islands grown on clean Si(001), suggesting a strong surfactant effect of Ga.}, language = {en} } @article{SokolowskiTintenBlomeBlumsetal., author = {Sokolowski-Tinten, Klaus and Blome, Christian and Blums, Juris and Shymanovich, Uladzimir and Nicoul, Matthieu and Cavalleri, Andrea and Tarasevitch, A. and Horn-von Hoegen, Michael and Kammler, Martin and von der Linde, D.}, title = {Ultrafast X-ray diffraction}, series = {Ultrafast Phenomena XIV}, volume = {79}, journal = {Ultrafast Phenomena XIV}, publisher = {Springer}, doi = {10.1007/3-540-27213-5_53}, pages = {170 -- 174}, abstract = {In the last few years the generation of femtosecond pulses in the X-ray regime has become possible. These ultrashort X-ray pulses have enabled femtosecond time- resolution to be extended to X-rays.}, language = {en} } @article{KammlerHullPortavoceetal., author = {Kammler, Martin and Hull, Robert and Portavoce, A. and Reuter, Mark C. and Ross, Frances M.}, title = {In-Situ Focused Ion Beam Micropatterning of Ge Islands}, series = {Microscopy and Microanalysis}, volume = {9}, journal = {Microscopy and Microanalysis}, number = {S02}, publisher = {Microscopy Society of America}, doi = {10.1017/S1431927603441214}, pages = {132 -- 134}, language = {en} } @article{FritzReisAdamsetal., author = {Fritz, D. M. and Reis, D. A. and Adams, B. and Akre, R. A. and Arthur, J. and Blome, Christian and Bucksbaum, P. H. and Cavalieri, A. L. and Engemann, S. and Fahy, S. and Falcone, R. W. and Fuoss, P. H. and Gaffney, K. J. and George, M. J. and Hajdu, J. and Hertlein, M. P. and Hillyard, P. B. and Horn-von Hoegen, Michael and Kammler, Martin and Kaspar, J. and Kienberger, R. and Krejcik, P. and Lee, S. H. and Lindenberg, A. M. and McFarland, B. and Meyer, D. and Montagne, T. and Murray, E. D. and Nelson, A. J. and Nicoul, Matthieu and Pahl, R. and Rudati, J. and Schlarb, H. and Siddons, D. P. and Sokolowski-Tinten, Klaus and Tschentscher, Th and von der Linde, D. and Hastings, J. B.}, title = {Ultrafast bond softening in bismuth: mapping a solid's interatomic potential with X-rays}, series = {Science}, volume = {315}, journal = {Science}, number = {5812}, publisher = {AAAS}, doi = {10.1126/science.1135009}, pages = {633 -- 636}, abstract = {Intense femtosecond laser excitation can produce transient states of matter that would otherwise be inaccessible to laboratory investigation. At high excitation densities, the interatomic forces that bind solids and determine many of their properties can be substantially altered. Here, we present the detailed mapping of the carrier density-dependent interatomic potential of bismuth approaching a solid-solid phase transition. Our experiments combine stroboscopic techniques that use a high-brightness linear electron accelerator-based x-ray source with pulse-by-pulse timing reconstruction for femtosecond resolution, allowing quantitative characterization of the interatomic potential energy surface of the highly excited solid.}, language = {en} } @inproceedings{SokolowskiTintenBlomeBlumsetal., author = {Sokolowski-Tinten, Klaus and Blome, Christian and Blums, Juris and Shymanovich, Uladzimir and Nicoul, Matthieu and Cavalleri, Andrea and Tarasevitch, A. and Horn-von Hoegen, Michael and Kammler, Martin and von der Linde, Dietrich}, title = {Ultrafast X-ray diffraction}, series = {Ultrafast Phenomena XIV}, volume = {79}, booktitle = {Ultrafast Phenomena XIV}, editor = {Kobayashi, Tetsuro}, publisher = {Springer}, address = {Berlin, Heidelberg}, isbn = {978-3-540-27213-7}, doi = {10.1007/3-540-27213-5_53}, pages = {170 -- 174}, abstract = {In the last few years the generation of femtosecond pulses in the X-ray regime has become possible. These ultrashort X-ray pulses have enabled femtosecond time- resolution to be extended to X-rays.}, language = {en} } @article{KammlerHornvonHoegenVossetal., author = {Kammler, Martin and Horn- von Hoegen, Michael and Voss, N. and Tringides, Michael C. and Menzel, Andreas and Conrad, E. H.}, title = {Si(001) step dynamics: A temporal low-energy electron diffraction study}, series = {Physical Review B}, volume = {65}, journal = {Physical Review B}, number = {7}, publisher = {APS}, doi = {10.1103/PhysRevB.65.075312}, abstract = {We present equilibrium measurements of the dynamics of steps on Si(001) using temporal electron-diffraction spectroscopy. Activation energies and the rate limiting kinetics are identified for 950K<~T<~1130K. Unlike previous studies at higher temperatures, we can exclude evaporation and condensation of atoms or dimers from the step edges as the rate limiting process in this temperature regime. The possible reason for this difference is discussed in terms of a crossover from different rate-limiting kinetics.}, language = {en} } @article{KrenzerHanischBlicharskiSchneideretal., author = {Krenzer, Boris and Hanisch-Blicharski, Anja and Schneider, Paul and Payer, Thomas and M{\"o}llenbeck, Simone and Osmani, O. and Kammler, Martin and Meyer, R. and Horn-von Hoegen, Michael}, title = {Phonon confinement effects in ultrathin epitaxial bismuth films on silicon studied by time-resolved electron diffraction}, series = {Physical Review B}, volume = {80}, journal = {Physical Review B}, number = {2}, publisher = {APS}, doi = {10.1103/PhysRevB.80.024307}, abstract = {The transient temperature evolution of ultrathin bismuth films, epitaxially grown on a silicon single crystal, upon femtosecond laser excitation is studied by time-resolved electron diffraction. The exponential decay of the film temperature is explained by phonon reflection at the interface, which results in a strongly reduced thermal conduction in the cross plane of the layered system. The thermal boundary conductance is found to be as low as 1273 W/(K cm2). Model calculations, including phonon confinement effects, explain the linear relationship between the observed film-temperature decay constant and the film thickness. Even for 2.5 nm thin films the phonon transmission probability across the interface is given by bulk properties. Our simulations show that phonon confinement effects are negligible for bismuth-film thicknesses larger than 1 nm.}, language = {en} } @article{KleinNabbefeldHattabetal., author = {Klein, C. and Nabbefeld, T. and Hattab, H. and Meyer, D. and Jnawali, G. and Kammler, Martin and Meyer zu Heringdorf, Frank-Joachim and Golla-Franz, A. and M{\"u}ller, B. H. and Schmidt, Thomas and Henzler, M. and Horn-von Hoegen, Michael}, title = {Lost in reciprocal space? Determination of the scattering condition in spot profile analysis low-energy electron diffraction}, series = {Review of scientific instruments}, volume = {82}, journal = {Review of scientific instruments}, number = {3}, publisher = {American Institute of Physics}, doi = {10.1063/1.3554305}, abstract = {The precise knowledge of the diffraction condition, i.e., the angle of incidence and electron energy, is crucial for the study of surface morphology through spot profile analysis low-energy electron diffraction (LEED). We demonstrate four different procedures to determine the diffraction condition: employing the distortion of the LEED pattern under large angles of incidence, the layer-by-layer growth oscillations during homoepitaxial growth, a G(S) analysis of a rough surface, and the intersection of facet rods with 3D Bragg conditions.}, language = {en} } @article{SchmidtKroegerClausenetal., author = {Schmidt, Thomas and Kr{\"o}ger, Roland and Clausen, T. and Falta, J. and Janzen, Andreas and Kammler, Martin and Kury, P. and Zahl, P. and Horn-von Hoegen, Michael}, title = {Surfactant-mediated epitaxy of Ge on Si(111): Beyond the surface}, series = {Applied Physics Letters}, volume = {86}, journal = {Applied Physics Letters}, number = {11}, publisher = {AIP}, doi = {10.1063/1.1882760}, abstract = {For a characterization of interface and "bulk" properties of Ge films grown on Si(111) by Sb surfactant-mediated epitaxy, grazing incidence x-ray diffraction and transmission electron microscopy have been used. The interface roughness, defect structure, and strain state have been investigated in dependence of film thickness and growth temperature. For all growth parameters, atomically smooth interfaces are observed. For thin Ge layers, about 75\% of the strain induced by the lattice mismatch is relaxed by misfit dislocations at the Ge/Si interface. Only a slight increase of the degree of relaxation is found for thicker films. At growth temperatures below about 600 °C, the formation of twins is observed, which can be avoided at higher temperatures.}, language = {en} } @article{FriggeWallKrenzeretal., author = {Frigge, Tim and Wall, S. and Krenzer, Boris and Wippermann, St. and Sanna, Simone and Klasing, Friedrich and Hanisch-Blicharski, Anja and Kammler, Martin and Schmidt, Wolf Gero and Horn-von Hoegen, Michael}, title = {Abstract - A Reply to the Comment by H. Shim et al.}, series = {Physical review letters}, volume = {111}, journal = {Physical review letters}, number = {14}, publisher = {American Physical Society}, doi = {10.1103/PhysRevLett.111.149602}, language = {en} } @article{CheeKammlerGrahametal., author = {Chee, See Wee and Kammler, Martin and Graham, Jeremy and Ross, Frances M. and Hull, Robert}, title = {Direct Imaging of Microstructural Changes in Si Induced by FIB-Patterning with Si ++ and Ga + Ions}, series = {Microscopy and Microanalysis}, volume = {17}, journal = {Microscopy and Microanalysis}, number = {S2}, publisher = {Cambridge University Press}, doi = {10.1017/S1431927611004156}, pages = {656 -- 657}, language = {en} } @article{WolfgrammAbbSampetal., author = {Wolfgramm, Alex and Abb, Valerius and Samp, Artur and Samp, Rafal and Hoffmann, Jens Christoph and M{\"u}ller, Rainer and Kammler, Martin}, title = {Structural and functional evolution of HKUST-1 nanoparticles induced by ball milling}, series = {Next Materials}, volume = {10}, journal = {Next Materials}, publisher = {Elsevier}, doi = {10.1016/j.nxmate.2025.101544}, pages = {7}, abstract = {In this study, the effect of post-synthetic ball milling on the structural and functional properties of as-synthesized nanoparticles of the copper-based metal-organic framework (MOF) HKUST-1 was investigated for the first time. Nanoparticles were synthesized using sodium formate as a capping agent. The crystalline particles were subjected to a controlled ball milling process, which induced significant structural changes. Powder X-ray diffraction (PXRD) revealed a reduction in crystallite size from 91 nm to 21 nm and the introduction of microstrain, partially disrupting the MOF's long-range crystalline order, as evidenced by peak broadening and the diminished intensity of high-angle reflections. Particle morphology pre- and post-milling was further studied with scanning electron microscopy (SEM) imaging, verifying a narrow particle size distribution of ± 22 nm after milling. Fourier-transform infrared spectroscopy (FTIR) indicated protonation of carboxylate groups in the larger pores of the framework, likely due to moisture incorporation during milling. Brunauer-Emmett-Teller (BET) surface area analysis showed a substantial decrease in specific surface area from 521 m²/g to 226 m²/g, suggesting a partial collapse of the porous framework. We discuss the applicability of ball milling as a versatile means of post-synthetic approach to reduce MOF particle sizes, a key element in the preparation of MOF-based thin films using inks or polymers.}, language = {en} }