Vladimir P. Jovanović

• PhD
• Research Associate Professor at Institute for Multidisciplinary Research, University of Belgrade, Serbia

Prolonged annealing of pentacene thin films in air leads to the formation of nano- and micro-scale rod-shaped structures at temperatures equal to or higher than 130 °C. Scanning electron microscopy measurements indicated their crystalline structure, while UV–vis absorption spectra revealed presence of different species of oxidized pentacene, includ...

The photoluminescence (PL) quenching mechanism of UV light and air-exposed amorphous thin films of 4,4′-bis(2,2-diphenylvinyl)-1,1′-biphenyl (DPVBi), a well-known hole-transport material used in organic light-emitting diodes, is studied. Thin films of DPVBi are stable when exposed to UV light in vacuum but tend to degrade if oxygen is present simul...

Owing to their low glass transition temperature, Tg, amorphous thin films of N,N′-bis(3-methylphenyl)-N,N′-bis(phenyl)benzidine (TPD) undergo morphological changes even at room temperature. It has been noticed previously that exposure to UV light can increase apparent Tg of TPD films and thus stabilize their morphology. However, the reason behind i...

Signatures of antiferromagnetism (AF) in the underdoped Ln2-xCexCuO4 (Ln=Nd,Pr,...) family are observed even for doping levels for which superconductivity exists. We have looked for a similar property in a different electron-doped cuprate family, Sr1-xLaxCuO2 , which consists of CuO2 planes separated by Sr/La atoms, and is exempt of the possible in...

We report a transport study down to 2 K and in high magnetic fields up to 20 T of a highly c-axis-oriented epitaxial thin film of electron-doped “infinite-layer” cuprate superconductor Sr1−xLaxCuO2 with Tc of 26 K. A 16 T magnetic field perpendicular to the ab plane of the film completely suppresses superconductivity, even at the lowest temperature...

Triacetone triperoxide (TATP) is a highly potent homemade explosive commonly used in terrorist attacks. Its detection poses a significant challenge due to its volatility, and the lack of portability of current sensing techniques. To address this issue, we propose a novel approach based on single-molecule TATP detection in the air using a device whe...

We demonstrate transitional dimensionality of discrete diffraction in radial-elliptical photonic lattices. Varying the order, characteristic structure size, and ellipticity of the Mathieu beams used for the photonic lattices generation, we control the shape of discrete diffraction distribution over the combination of the radial direction with the c...

We studied the in-plane angular magnetoresistance (AMR), in the normal state, of underdoped superconducting Sr1-xLaxCuO2 , which has the simplest crystal structure among cuprates. The measurements of two underdoped thin films with different dopings were performed in intense magnetic field H (up to 22 T). The longitudinal magnetoresistance at temper...

The electrical current properties of single-molecule sensing devices based on electronic (tunneling) transport strongly depend on molecule frontier orbital energy, spatial distribution, and position with respect to the electrodes. Here, we present an analysis of the bias dependence of molecule frontier orbital properties at an exemplar case of DNA...

We studied the in-plane angular magnetoresistance (AMR), in the normal state, of underdoped superconducting Sr1–xLaxCuO2, which has the simplest crystal structure among cuprates. The measurements of two underdoped thin films with different dopings were performed in intense magnetic field H (up to 22 T). The longitudinal magnetoresistance at tempera...

The requirement for controllable frontier orbital energy shift in single-molecule devices based on electronic (tunneling) transport yielded several rules for device design that lean on molecular level pinning to the electrochemical potential of nano-electrodes. We previously found that the pinning (designated as the strong pinning) was the conseque...

Functionalization of electrodes is a wide‐used strategy in various applications ranging from single‐molecule sensing and protein sequencing, to ion trapping, to desalination. We demonstrate, employing non‐equilibrium Green′s function formalism combined with density functional theory, that single‐species (N, H, S, Cl, F) termination of graphene nano...

Fast, reliable and inexpensive DNA sequencing is an important pursuit in healthcare, especially in personalized medicine with possible deep societal impacts. Despite significant progress of various nanopore-based sequencing configurations, challenges that remain in resolution and chromosome-size long readout call for new approaches. Here we found s...

Aim: To characterize stem cells originating from different dental tissues (apical papilla [SCAP], dental follicle [DFSC], and pulp [DPSC]) and test the capacity of Raman microspectroscopy to distinguish between the three dental stem cell types. Methods: SCAP, DFSC, and DPSC cultures were generated from three immature wisdom teeth originating fro...

Single-molecule biosensing, with a promise of being applied in protein and DNA sequencing, could be achieved using tunneling current approach. Electrode-molecule-electrode tunneling current critically depends on whether molecular levels contribute to electronic transport or not. Here we found employing DFT and Non-Equilibrium Green's Function forma...

Fast, reliable and inexpensive DNA sequencing is an important pursuit in biotechnology with potentially profound societal impact due to its implications on personalized medicine. High resolution and specificity are key cornerstones of technological progress of DNA sequencing, currently enabled by various nanopore current measuring methods. Here we...

There is an ongoing interest in organic materials due to their application in various organic electronic devices. However stability of organic materials limits their potential use. They are prone to degradation both during the working life and storage. One of the main causes is extrinsic degradation, under the influence of oxygen and moisture. This...

U ovom radu je prikazana studija mehanizma gašenja fotoluminescencije (PL) tankih amorfnih filmova N,N′-bis(3-methylphenyl)-N,N′-bis(phenyl)benzidine (TPD) izloženih UV zračenju u vazduhu. TPD je organski molekul koji se često koristi u izradi organskih svetlećih dioda (OLED). Prilikom izlaganja TPD filmova UV zračenju u vazduhu, dolazi do fotooksi...

The mechanism of photoluminescence (PL) quenching of thin amorphous N,N′-bis(3-methylphenyl)- N,N′-bis(phenyl)benzidine (TPD) films exposed to UV light in air is studied. TPD is small organic molecule widely used in production of organic light emmiting devices (OLEDs). Photoluminescence of TPD films decays exponentially with time of irradiation, i....

We report a study on the superconducting properties of e-doped Sr0.88La0.12CuO2 (SLCO) thin films. SLCO has an infinite layer structure consisting of CuO2 planes, 3.40 Å apart, separated by Sr, La planes. Highly c-axis oriented thin films, with a critical temperature of 22–23 K, were epitaxially grown by sputtering. Their resistive transition hardl...

The in-plane penetration depth of Sr0.88La0.12CuO2+x thin films at various doping obtained from oxygen reduction has been measured, using ac-susceptibility measurements. For the higher doping samples, the superfluid density deviates strongly from the s-wave behavior, suggesting, in analogy with other electron-doped cuprates, a contribution from a n...

The in-plane penetration depth of Sr$_{0.88}$La$_{0.12}$CuO$_{2+x}$ thin films at various doping obtained from oxygen reduction has been measured, using AC susceptibility measurements. For the higher doping samples, the superfluid density deviates strongly from the s-wave behavior, suggesting, in analogy with other electron-doped cuprates, a contri...

We have epitaxially grown c-axis oriented SrxLa1-xCuO2 thin films by rf sputtering on KTaO3 substrates with x = 0.12. The as-grown deposits are insulating and a series of superconducting films with various Tc(R=0) up to 26 K have been obtained by in-situ oxygen reduction. Transport measurements in the ab plane of these samples have been undertaken....

Single-phase, c-axis oriented, e-doped, Sr1−xLaxCuO2 thin films were epitaxially grown on KTaO3 and DyScO3 substrates by reactive rf sputtering. As-grown films being insulating due to oxygen excess, oxygen reduction is necessary to observe superconductivity. Two different procedures were employed to reach superconductivity. On one hand an in situ r...

Single phase, c-axis oriented, e-doped, Sr1-xLaxCuO2 thin films were epitaxially grown on KTaO3 and DyScO3 substrates by reactive rf sputtering. As-grown films being insulating due to oxygen excess, oxygen reduction is necessary to observe superconductivity. Two different procedures were employed to reach superconductivity. On one hand an in-situ r...

We calculate self-consistently in-plane superfluid density in planar organic superconductors for three types of pairing symmetry: dx2-y2, dxy-like and extended s-wave pairing. Assuming strong dimerization, we consider a single band model with elliptical Fermi surface to evaluate the temperature dependence in κ-(BEDT–TTF)2X compounds for those types...

The nature of superconductivity in planar organics is still a controversial problem. We investigate two types of d-wave and extended s-wave pairing proposed theoretically in a model of κ-(BEDT–TTF)2X organic superconductors. As probes of the pairing symmetry, we calculate the density of states, the tunnelling conductance, the specific heat, and the...

The nature of superconductivity in planar organics is still a controversial problem. We investigate theoretically d-wave and anisotropic s-wave pairing in k ¡(BEDT ¡TTF)2X compounds. Assuming strong dimerization, we consider a single band model with elliptical Fermi surface to calculate density of states, specific heat and spin susceptibility as fu...