“Orbital-hybridization-driven charge density wave transition in CsV₃Sb₅, kagome superconductor”. Han S, Tang CS, Li L, Liu Y, Liu H, Gou J, Wu J, Zhou D, Yang P, Diao C, Ji J, Bao J, Zhang L, Zhao M, Milošević, MV, Guo Y, Tian L, Breese MBH, Cao G, Cai C, Wee ATS, Yin X, Advanced materials , 1 (2022). http://doi.org/10.1002/ADMA.202209010
Abstract: Owing to its inherent non-trivial geometry, the unique structural motif of the recently discovered kagome topological superconductor AV(3)Sb(5) (A = K, Rb, Cs) is an ideal host of diverse topologically non-trivial phenomena, including giant anomalous Hall conductivity, topological charge order, charge density wave (CDW), and unconventional superconductivity. Despite possessing a normal-state CDW order in the form of topological chiral charge order and diverse superconducting gaps structures, it remains unclear how fundamental atomic-level properties and many-body effects including Fermi surface nesting, electron-phonon coupling, and orbital hybridization contribute to these symmetry-breaking phenomena. Here, the direct participation of the V3d-Sb5p orbital hybridization in mediating the CDW phase transition in CsV3Sb5 is reported. The combination of temperature-dependent X-ray absorption and first-principles studies clearly indicates the inverse Star-of-David structure as the preferred reconstruction in the low-temperature CDW phase. The results highlight the critical role that Sb orbitals play and establish orbital hybridization as the direct mediator of the CDW states and structural transition dynamics in kagome unconventional superconductors. This is a significant step toward the fundamental understanding and control of the emerging correlated phases from the kagome lattice through the orbital interactions and provides promising approaches to novel regimes in unconventional orders and topology.
Keywords: A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)
Impact Factor: 29.4
Times cited: 1
DOI: 10.1002/ADMA.202209010
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“Vacancy clustering effect on the electronic and transport properties of bilayer graphene nanoribbons”. Miranda LP, da Costa DR, Peeters FM, Costa Filho RN, Nanotechnology 34, 055706 (2023). http://doi.org/10.1088/1361-6528/AC9F50
Abstract: Experimental realizations of two-dimensional materials are hardly free of structural defects such as e.g. vacancies, which, in turn, modify drastically its pristine physical defect-free properties. In this work, we explore effects due to point defect clustering on the electronic and transport properties of bilayer graphene nanoribbons, for AA and AB stacking and zigzag and armchair boundaries, by means of the tight-binding approach and scattering matrix formalism. Evident vacancy concentration signatures exhibiting a maximum amplitude and an universality regardless of the system size, stacking and boundary types, in the density of states around the zero-energy level are observed. Our results are explained via the coalescence analysis of the strong sizeable vacancy clustering effect in the system and the breaking of the inversion symmetry at high vacancy densities, demonstrating a similar density of states for two equivalent degrees of concentration disorder, below and above the maximum value.
Keywords: A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)
Impact Factor: 3.5
Times cited: 1
DOI: 10.1088/1361-6528/AC9F50
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“Wave-packet propagation in a graphene geometric diode”. Andelkovic M, Rakhimov KY, Chaves A, Berdiyorov GR, Milošević, MV, Physica. E: Low-dimensional systems and nanostructures 147, 115607 (2023). http://doi.org/10.1016/J.PHYSE.2022.115607
Abstract: Dynamics of electron wave-packets is studied using the continuum Dirac model in a graphene geometric diode where the propagation of the wave packet is favored in certain direction due to the presence of geometric constraints. Clear rectification is obtained in the THz frequency range with the maximum rectification level of 3.25, which is in good agreement with recent experiments on graphene ballistic diodes. The rectification levels are considerably higher for systems with narrower channels. In this case, the wave packet transmission probabilities and rectification rate also strongly depend on the energy of the incident wave packet, as a result of the quantum nature of energy levels along such channels. These findings can be useful for fundamental understanding of the charge carrier dynamics in graphene geometry diodes.
Keywords: A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)
Impact Factor: 3.3
Times cited: 1
DOI: 10.1016/J.PHYSE.2022.115607
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“Cation-controlled permeation of charged polymers through nanocapillaries”. Faraji F, Neek-Amal M, Neyts EC, Peeters FM, Physical review E 107, 034501 (2023). http://doi.org/10.1103/PHYSREVE.107.034501
Abstract: Molecular dynamics simulations are used to study the effects of different cations on the permeation of charged polymers through flat capillaries with heights below 2 nm. Interestingly, we found that, despite being monovalent, Li+ , Na+ , and K+ cations have different effects on polymer permeation, which consequently affects their transmission speed throughout those capillaries. We attribute this phenomenon to the interplay of the cations' hydration free energies and the hydrodynamic drag in front of the polymer when it enters the capillary. Different alkali cations exhibit different surface versus bulk preferences in small clusters of water under the influence of an external electric field. This paper presents a tool to control the speed of charged polymers in confined spaces using cations.
Keywords: A1 Journal article; Condensed Matter Theory (CMT); Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Impact Factor: 2.4
Times cited: 1
DOI: 10.1103/PHYSREVE.107.034501
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“Flattening conduction and valence bands for interlayer excitons in a moire MoS₂/WSe₂, heterobilayer”. Conti S, Chaves A, Pandey T, Covaci L, Peeters FM, Neilson D, Milošević, MV, Nanoscale , 1 (2023). http://doi.org/10.1039/D3NR01183F
Abstract: We explore the flatness of conduction and valence bands of interlayer excitons in MoS2/WSe2 van der Waals heterobilayers, tuned by interlayer twist angle, pressure, and external electric field. We employ an efficient continuum model where the moire pattern from lattice mismatch and/or twisting is represented by an equivalent mesoscopic periodic potential. We demonstrate that the mismatch moire potential is too weak to produce significant flattening. Moreover, we draw attention to the fact that the quasi-particle effective masses around the Gamma-point and the band flattening are reduced with twisting. As an alternative approach, we show (i) that reducing the interlayer distance by uniform vertical pressure can significantly increase the effective mass of the moire hole, and (ii) that the moire depth and its band flattening effects are strongly enhanced by accessible electric gating fields perpendicular to the heterobilayer, with resulting electron and hole effective masses increased by more than an order of magnitude – leading to record-flat bands. These findings impose boundaries on the commonly generalized benefits of moire twistronics, while also revealing alternative feasible routes to achieve truly flat electron and hole bands to carry us to strongly correlated excitonic phenomena on demand.
Keywords: A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT)
Impact Factor: 6.7
Times cited: 1
DOI: 10.1039/D3NR01183F
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“High thermoelectric figure of merit in p-type Mg₃Si₂Te₆: role of multi-valley bands and high anharmonicity”. Pandey T, Peeters FM, Milošević, MV, Journal of materials chemistry C : materials for optical and electronic devices 11, 11185 (2023). http://doi.org/10.1039/D3TC02169F
Abstract: Silicon-based materials are attractive for thermoelectric applications due to their thermal stability, chemical inertness, and natural abundance of silicon. Here, using a combination of first-principles and Boltzmann transport calculations we report the thermoelectric properties of the recently synthesized compound Mg3Si2Te6. Our analysis reveals that Mg3Si2Te6 is a direct bandgap semiconductor with a bandgap of 1.6 eV. The combination of heavy and light valence bands, along with a high valley degeneracy, results in a large power factor under p-type doping. We also find that Mg is weakly bonded both within and between the layers, leading to low phonon group velocities. The vibrations of the Mg atoms are localized and make a significant contribution to phonon-phonon scattering. This high anharmonicity, coupled with low phonon group velocity, results in a low lattice thermal conductivity of & kappa;(l) = 0.5 W m(-1) K-1 at room temperature, along the cross-plane direction. Combining excellent electronic transport properties and low & kappa;(l), p-type Mg3Si2Te6 achieves figure-of-merit (zT) values greater than 1 at temperatures above 600 K. Specifically, a zT of 2.0 is found at 900 K along the cross-plane direction. Our findings highlight the importance of structural complexity and chemical bonding in electronic and phonon transport, providing guiding insights for further design of Si-based thermoelectrics.
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 6.4
Times cited: 1
DOI: 10.1039/D3TC02169F
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“Multiband flattening and linear Dirac band structure in graphene with impurities”. Ahmadkhani S, Alihosseini M, Ghasemi S, Ahmadabadi I, Hassani N, Peeters FM, Neek-Amal M, Physical review B 107, 075401 (2023). http://doi.org/10.1103/PHYSREVB.107.075401
Abstract: Flat bands in the energy spectrum have attracted a lot of attention in recent years because of their unique properties and promising applications. Special arrangement of impurities on monolayer graphene are proposed to generate multiflat bands in the electronic band structure. In addition to the single midgap states in the spectrum of graphene with low hydrogen density, we found closely spaced bands around the Fermi level with increasing impurity density, which are similar to discrete lines in the spectrum of quantum dots, as well as the unusual Landau-level energy spectrum of graphene in the presence of a strong magnetic field. The presence of flat bands crucially depends on whether or not there are odd or even electrons of H(F) atoms bound to graphene. Interestingly, we found that a fully hydrogenated (fluoridated) of a hexagon of graphene sheet with six hydrogen (fluorine) atoms sitting on top and bottom in consecutive order exhibits Dirac cones in the electronic band structure with a 20% smaller Fermi velocity as compared to the pristine graphene. Functionalizing graphene introduces various C-C bond lengths resulting in nonuniform strains. Such a nonuniform strain may induce a giant pseudomagnetic field in the system, resulting in quantum Hall effect.
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 3.7
Times cited: 1
DOI: 10.1103/PHYSREVB.107.075401
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“Influence of neutron irradiation on X-ray diffraction, Raman spectrum and photoluminescence from pyrolytic and hot-pressed hexagonal boron nitride”. Zhou S, Xu W, Xiao Y, Xiao H, Zhang J, Wang Z, He G, Liu J, Li Y, Peeters FM, Journal of luminescence 263, 120118 (2023). http://doi.org/10.1016/J.JLUMIN.2023.120118
Abstract: Hexagonal boron nitride (hBN) is considered as an ideal semiconductor material for solid-state neutron detector, owing to its large neutron scattering section because of the low atomic number of B and excellent physical properties. Here we study the influence of neutron irradiation on crystal structure and on intermediate energy state (IMES) levels induced by the presence of impurities and defects in hBN. Large-size and thick pyrolytic and hot-pressed hBN (PBN and HBN) samples, which can be directly applied for neutron detector devices, are prepared and bombarded by neutrons with different irradiation fluences. The SEM and TEM are used to observe the sample difference of PBN and HBN. X-ray diffraction and Raman spectroscopy are applied to examine the influence of neutron irradiation on lattice structures along different crystal directions of PBN and HBN samples. Photoluminescence (PL) is employed to study the effect of neutron irradiation on IMESs in these samples. We find that the neutron irradiation does not alter the in-plane lattice structures of both PBN and HBN samples, but it can release the inter-layer tensions induced by sample growth of the PBN samples. Interestingly and surprisingly, the neutron irradiation does not affect the IMES levels responsible for PL generation, where PL is attributed mainly from phonon-assisted radiative electron-hole coupling for both PBN and HBN samples. Furthermore, the results indicate that the neutron irradiation can weaken the effective carrier-phonon coupling and exciton transitions in PBN and HBN samples. Overall, both PBN and HBN samples show some degree of the resistance to neutron irradiation in terms of these basic physical properties. The interesting and important findings from this work can help us to gain an in-depth understanding of the influence of neutron irradiation on basic physical properties of hBN materials. These effects can be taken into account when designing and applying the hBN materials for neutron detectors.
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 3.6
Times cited: 1
DOI: 10.1016/J.JLUMIN.2023.120118
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“Intra-zero-energy Landau level crossings in bilayer graphene at high electric fields”. Xiang F, Gupta A, Chaves A, Krix ZE, Watanabe K, Taniguchi T, Fuhrer MS, Peeters FM, Neilson D, Milošević, MV, Hamilton AR, Nano letters 23, 9683 (2023). http://doi.org/10.1021/ACS.NANOLETT.3C01456
Abstract: The highly tunable band structure of the zero-energy Landau level (zLL) of bilayer graphene makes it an ideal platform for engineering novel quantum states. However, the zero-energy Landau level at high electric fields has remained largely unexplored. Here we present magnetotransport measurements of bilayer graphene in high transverse electric fields. We observe previously undetected Landau level crossings at filling factors nu = -2, 1, and 3 at high electric fields. These crossings provide constraints for theoretical models of the zero-energy Landau level and show that the orbital, valley, and spin character of the quantum Hall states at high electric fields is very different from low electric fields. At high E, new transitions between states at nu = -2 with different orbital and spin polarization can be controlled by the gate bias, while the transitions between nu = 0 -> 1 and nu = 2 -> 3 show anomalous behavior.
Keywords: A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)
Impact Factor: 10.8
Times cited: 1
DOI: 10.1021/ACS.NANOLETT.3C01456
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“Tuning of exciton type by environmental screening”. Lima ILC, Milošević, MV, Peeters FM, Chaves A, Physical review B 108, 115303 (2023). http://doi.org/10.1103/PHYSREVB.108.115303
Abstract: We theoretically investigate the binding energy and electron-hole (e-h) overlap of excitonic states confined at the interface between two-dimensional materials with type-II band alignment, i.e., with lowest conduction and highest valence band edges placed in different materials, arranged in a side-by-side planar heterostructure. We propose a variational procedure within the effective mass approximation to calculate the exciton ground state and apply our model to a monolayer MoS2/WS2 heterostructure. The role of nonabrupt interfaces between the materials is accounted for in our model by assuming a WxMo1-xS2 alloy around the interfacial region. Our results demonstrate that (i) interface-bound excitons are energetically favorable only for small interface thickness and/or for systems under high dielectric screening by the materials surrounding the monolayer, and that (ii) the interface exciton binding energy and its e-h overlap are controllable by the interface width and dielectric environment.
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 3.7
Times cited: 1
DOI: 10.1103/PHYSREVB.108.115303
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“Interlink between Abnormal Water Imbibition in Hydrophilic and Rapid Flow in Hydrophobic Nanochannels”. Zhou R, Neek-Amal M, Peeters FM, Bai B, Sun C, Physical Review Letters 132, 184001 (2024). http://doi.org/10.1103/PhysRevLett.132.184001
Abstract: Nanoscale extension and refinement of the Lucas-Washburn model is presented with a detailed analysis of recent experimental data and extensive molecular dynamics simulations to investigate rapid water flow and water imbibition within nanocapillaries. Through a comparative analysis of capillary rise in hydrophilic nanochannels, an unexpected reversal of the anticipated trend, with an abnormal peak, of imbibition length below the size of 3 nm was discovered in hydrophilic nanochannels, surprisingly sharing the same physical origin as the well-known peak observed in flow rate within hydrophobic nanochannels. The extended imbibition model is applicable across diverse spatiotemporal scales and validated against simulation results and existing experimental data for both hydrophilic and hydrophobic
Keywords: A1 Journal Article; CMT
Impact Factor: 8.6
Times cited: 1
DOI: 10.1103/PhysRevLett.132.184001
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“Tailoring weak and metallic phases in a strong topological insulator by strain and disorder : conductance fluctuations signatures”. Shafiei M, Fazileh F, Peeters FM, Milošević, MV, Physical review B 109, 045129 (2024). http://doi.org/10.1103/PHYSREVB.109.045129
Abstract: Transport measurements are readily used to probe different phases in disordered topological insulators (TIs), where determining topological invariants explicitly is challenging. On that note, universal conductance fluctuations (UCF) theory asserts the conductance G for an ensemble has a Gaussian distribution, and that standard deviation 8G depends solely on the symmetries and dimensions of the system. Using a real-space tight -binding Hamiltonian on a system with Anderson disorder, we explore conductance fluctuations in a thin Bi2Se3 film and demonstrate the agreement of their behavior with UCF hypotheses. We further show that magnetic field applied out-of-plane breaks the time -reversal symmetry and transforms the system's Wigner-Dyson class from root symplectic to unitary, increasing 8G by 2. Finally, we reveal that while Bi2Se3 is a strong TI, weak TI and metallic phases can be stabilized in presence of strain and disorder, and detected by monitoring the conductance fluctuations.
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 3.7
Times cited: 1
DOI: 10.1103/PHYSREVB.109.045129
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“Ab initio approach to superexchange interactions in alkali doped fullerides AC60”. Nikolaev AV, Michel KH, AIP conference proceedings
T2 –, 18th International Winterschool/Euroconference on Electronic Properties, of Novel Materials, MAR 06-JUN 13, 2004, Kirchberg, AUSTRIA , 393 (2004). http://doi.org/10.1063/1.1812115
Abstract: The superexchange interactions between the fullerenes arise as a result of the electron transfer from the C-60 molecule to the alkali atom and back. We present a scheme, which is a configuration interaction approach based on the valence bond (Heitler-London) method. The effect of superexchange is described together with chemical bonding by constructing and solving a secular equation, rather than by using a perturbation treatment. We have considered 180degrees and 90degrees superexchange for the C-60 Cs-C-60 pathways. The calculations account for unusual electronic properties of polymer orthorhombic and quenched cubic phases of CsC60: two lines in nuclear magnetic resonance experiments, the development of a spin-singlet ground state and a decrease of magnetic susceptibility as T-->0.
Keywords: P1 Proceeding; Condensed Matter Theory (CMT)
DOI: 10.1063/1.1812115
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Verhulst SL, de Backer J, Van Gaal L, de Backer W, Desager K (2008) Adenotonsillectomy as first-line treatment for sleep-disordered breathing in obese children. New York, 1399
Keywords: L1 Letter to the editor; Condensed Matter Theory (CMT); Laboratory Experimental Medicine and Pediatrics (LEMP)
Impact Factor: 13.204
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“Angular confinement and direction-dependent transmission in graphene nanostructures with magnetic barriers”. Masir MR, Vasilopoulos P, Matulis A, Peeters FM, AIP conference proceedings 1199, 363 (2009). http://doi.org/10.1063/1.3295453
Abstract: We evaluate the transmission through magnetic barriers in graphene-based nanostructures. Several particular cases are considered: a magnetic step, single and double barriers, delta -function barriers as well as barrier structures with inhomogeneous magnetic field profiles but with average magnetic field equal to zero. The transmission exhibits a strong dependence on the direction of the incident wave vector. In general the resonant structure of the transmission is significantly more pronounced for (Dirac) electrons with linear spectrum compared to that for electrons with a parabolic one.
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
DOI: 10.1063/1.3295453
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“Anisotropic packing of C-70 molecules in carbon nanotubes”. Verberck B, Michel KH, Physica status solidi B-basic solid state physics 244, 4279 (2007). http://doi.org/10.1002/pssb.200776144
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 1.674
DOI: 10.1002/pssb.200776144
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“Band structure, density of states, and transmission in graphene bilayer superlattices”. Barbier M, Vasilopoulos P, Peeters FM, Pereira JM, AIP conference proceedings 1199, 547 (2009). http://doi.org/10.1063/1.3295550
Abstract: The energy spectrum and density of states of graphene bilayer superlattices (SLs) are evaluated. We take into account doping and/or gating of the layers as well as tunnel coupling between them. In addition, we evaluate the transmission through such SLs and through single or double barriers. The transmission exhibits a strong dependence on the direction of the incident wave vector.
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
DOI: 10.1063/1.3295550
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“Branch current behavior at two level anti-crossings in vertical quantum dot single-particle spectra”. Payette C, Austing DG, Yu G, Gupta JA, Nair SV, Partoens B, Amaha S, Tarucha S, AIP conference proceedings 1199, 271 (2010). http://doi.org/10.1063/1.3295404
Abstract: We study single-electron-elastic-resonant-tunneling through two weakly coupled vertical quantum dots and investigate the branch current behavior at anti-crossings between two single-particle energy levels in the constituent dot spectra that are induced to approach each other by application of an out-of-dot-plane magnetic field. We observe both the familiar case of monotonic transfer of the resonant current strengths between the two branches as well as the less familiar case of concurrent enhancement and suppression (ideally complete cancellation) of the resonant current in the two branches. These two situations can be explained in terms of a simple coherent tunneling model. ©2009 American Institute of Physics
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
DOI: 10.1063/1.3295404
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“Cascades of multiheaded chimera states for coupled phase oscillators”. Maistrenko YL, Vasylenko A, Sudakov O, Levchenko R, Maistrenko VL, International journal of bifurcation and chaos in applied sciences and engineering 24, 1440014 (2014). http://doi.org/10.1142/S0218127414400148
Abstract: Chimera state is a recently discovered dynamical phenomenon in arrays of nonlocally coupled oscillators, that displays a self-organized spatial pattern of coexisting coherence and incoherence. We discuss the appearance of the chimera states in networks of phase oscillators with attractive and with repulsive interactions, i.e. when the coupling respectively favors synchronization or works against it. By systematically analyzing the dependence of the spatiotemporal dynamics on the level of coupling attractivity/repulsivity and the range of coupling, we uncover that different types of chimera states exist in wide domains of the parameter space as cascades of the states with increasing number of intervals of irregularity, so-called chimera's heads. We report three scenarios for the chimera birth: (1) via saddle-node bifurcation on a resonant invariant circle, also known as SNIC or SNIPER, (2) via blue-sky catastrophe, when two periodic orbits, stable and saddle, approach each other creating a saddle-node periodic orbit, and (3) via homoclinic transition with complex multistable dynamics including an “eight-like” limit cycle resulting eventually in a chimera state.
Keywords: A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)
Impact Factor: 1.329
DOI: 10.1142/S0218127414400148
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“Characterization and modeling of single-particle energy levels and resonant currents in a coherent quantum dot mixer”. Austing DG, Payette C, Yu G, Gupta JA, Aers GC, Nair SV, Partoens B, Amaha S, Tarucha S, AIP conference proceedings
T2 –, 30th International Conference on the Physics of Semiconductors (ICPS-30), JUL 25-30, 2010, Seoul, SOUTH KOREA , 1 (2011). http://doi.org/10.1063/1.3666692
Abstract: We characterize and model the single-particle energy level position and resonant current strength at a three-level crossing in a coherent mixer composed of two weakly coupled vertical quantum dots. In addition to clear anticrossing behavior, an otherwise strong resonance is completely extinguished at the center of the crossing. Despite the strong variation in energy level position and resonant current strength throughout the crossing region, the resonance widths and the sum of the branch currents are found to be approximately constant.
Keywords: P1 Proceeding; Condensed Matter Theory (CMT)
DOI: 10.1063/1.3666692
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“Classical atomic bilayers”. Peeters FM, Partoens B, Schweigert VA, Schweigert IV Plenum Press, New York, page 523 (1998).
Keywords: H1 Book chapter; Condensed Matter Theory (CMT)
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“Classical nature of quantum dots in a magnetic field”. Anisimovas E, Matulis A, Peeters FM, Acta physica Polonica: A: general physics, solid state physics, applied physics 107, 188 (2005)
Abstract: A quasiclassical theory of few-electron quantum dots in a strong magnetic field is developed. The ground state energy and the corresponding many-electron wave function are obtained and used to derive a universal relation of critical magnetic fields and calculate the currents and the density-current correlation function.
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 0.469
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“Clinical applications of image-based airway computational fluid dynamics: assessment of inhalation medication and endobronchial devices”. de Backer JW, Vos WG, Germonpré, P, Salgado R, Parizel PM, de Backer W, Proceedings of the Society of Photo-optical Instrumentation Engineers 7262, 72621p (2009). http://doi.org/10.1117/12.811476
Abstract: Computational fluid dynamics (CFD) is a technique that is used increasingly in the biomedical field. Solving the flow equations numerically provides a convenient way to assess the efficiency of therapies and devices, ranging from cardiovascular stents and heart valves to hemodialysis workflows. Also in the respiratory field CFD has gained increasing interest, especially through the combination of three dimensional image reconstruction which results in highend patient-specific models. This paper provides an overview of clinical applications of CFD through image based modeling, resulting from recent studies performed in our center. We focused on two applications: assessment of the efficiency of inhalation medication and analysis of endobronchial valve placement. In the first application we assessed the mode of action of a novel bronchodilator in 10 treated patients and 4 controls. We assessed the local volume increase and resistance change based on the combination of imaging and CFD. We found a good correlation between the changes in volume and resistance coming from the CFD results and the clinical tests. In the second application we assessed the placement and effect of one way endobronchial valves on respiratory function in 6 patients. We found a strong patientspecific result of the therapy where in some patients the therapy resulted in complete atelectasis of the target lobe while in others the lobe remained inflated. We concluded from these applications that CFD can provide a better insight into clinically relevant therapies.
Keywords: A3 Journal article; Condensed Matter Theory (CMT); Antwerp Surgical Training, Anatomy and Research Centre (ASTARC); Laboratory Experimental Medicine and Pediatrics (LEMP)
DOI: 10.1117/12.811476
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“Continuum versus discrete flux behaviour in large mesoscopic Bi2Sr2CaCu2O8+\delta disks”. Connolly MR, Bemding SJ, Milošević, MV, Clem JR, Tamegai T, Physica: C : superconductivity 470, S896 (2010). http://doi.org/10.1016/j.physc.2009.11.117
Abstract: We have used scanning Hall probe and local Hall magnetometry measurements to map flux profiles in superconducting Bi2Sr2CaCu2O8+δ disks whose diameters span the crossover between the bulk and mesoscopic vortex regimes. The behaviour of large disks (greater-or-equal, slanted20 μm diameter) is well described by analytic models that assume a continuous distribution of flux in the sample. Small disks (less-than-or-equals, slant10 μm diameter), on the other hand, exhibit clear signatures of the underlying discrete vortex structure as well as competition between triangular Abrikosov ordering and the formation of shell structures driven by interactions with circulating edge currents. At low fields we are able to directly observe the characteristic mesoscopic compression of vortex clusters which is linked to oscillations in the diameter of the vortex dome in increasing magnetic fields. At higher fields, where single vortex resolution is lost, we are still able to track configurational changes in the vortex patterns, since competing vortex orders impose unmistakable signatures on local magnetisation curves. Our observations are in excellent agreement with molecular-dynamics numerical simulations which lead us to a natural definition of the lengthscale for the crossover between discrete and continuum behaviour in our system.
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 1.404
DOI: 10.1016/j.physc.2009.11.117
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“Correlation between a remote electron and a two-dimensional electron gas in resonant tunneling devices”. Kato H, Peeters FM, , 843 (2001)
Keywords: P3 Proceeding; Condensed Matter Theory (CMT)
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“Density dependence of the rectification of vortex motion in a circular asymmetric channel”. Lin NS, Misko VR, Heitmann TW, Yu K, Plourde BLT, Physica: C : superconductivity 479, 137 (2012). http://doi.org/10.1016/j.physc.2011.12.028
Abstract: We study the rectification of vortex motion in an asymmetric ring channel in a Corbino setup. With an applied ac current, the motion of vortices in the channel is rectified by the asymmetric potential and induces a dc net flow. The net flow in such a system strongly depends on vortex density, and we distinguish “single-vortex'' rectification regime (for low density, when each vortex is rectified individually) determined by the potential-energy landscape inside each cell of the channel and ”multi-vortex'', or "collective'', rectification (high density case) when the interaction between vortices becomes important. (C) 2012 Elsevier B.V. All rights reserved.
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 1.404
DOI: 10.1016/j.physc.2011.12.028
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“Density functional theory approach to artificial molecules”. Partoens B, Peeters FM, , 128 (2001)
Keywords: P1 Proceeding; Condensed Matter Theory (CMT)
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“Different temperature dependence of the phase boundary for multivortex and giant vortex states in mesoscopic superconductors”. Baelus BJ, Kanda A, Peeters FM, Ootuka Y, Kadowaki, AIP conference proceedings
T2 –, 24th International Conference on Low Temperature Physics (LT24), AUG 10-17, 2005, Orlando, FL , 743 (2006)
Abstract: Within the framework of the nonlinear Ginzburg-Landau theory, we calculated the full phase diagram for a superconducting disk with radius R = 4 (T = 0) and we studied the behavior of the penetration and expulsion fields as a function of temperature for multivortex and giant vortex states.
Keywords: P1 Proceeding; Condensed Matter Theory (CMT)
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“Domain coexistence of magnetism and superconductivity : appearance of confined vortex loops”. Doria MM, de Romaguera ARC, Milošević, MV, Peeters FM, Journal of physics : conference series 97, 012070 (2008). http://doi.org/10.1088/1742-6596/97/1/012070
Abstract: A magnetic moment inside an extreme type II superconductor can have three, but not one or two, confined vortex loops near to the core. For a sub-micron superconducting particle the confined vortex loops eventually break up and reach the surface turning into external vortex pairs.
Keywords: P1 Proceeding; Condensed Matter Theory (CMT)
DOI: 10.1088/1742-6596/97/1/012070
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“Driven quasi-on-dimensional classical electron gas in the presence of a constriction: pinning and depinning”. Piacente G, Peeters FM, Physica. E: Low-dimensional systems and nanostructures 34, 224 (2006). http://doi.org/10.1016/j.physe.2006.03.040
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 2.221
DOI: 10.1016/j.physe.2006.03.040
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