308 citations · 2.5k across the 63 of their papers we have counts for
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Negative c-axis magnetoresistance in graphite
Y. Kopelevich, R. R. da Silva, J. C. Medina Pantoja +1
We have studied the c-axis interlayer magnetoresistance (ILMR), R_c(B) in graphite. The measurements have been performed on strongly anisotropic highly oriented pyrolytic graphite…
Giant flexoelectric effect in two-dimensional boron-nitride sheets
Ivan Naumov, Alexander M. Bratkovsky, V. Ranjan
We find, with the use of first-principles calculations, that a single-atom-thick boron-nitride (BN) sheet exhibits an unusual nonlinear electromechanical effect: it becomes macrosc…
Auger-mediated radiative recombination in three-dimensional silicon/silicon-germanium nanostructures
E. -K. Lee, D. J. Lockwood, J. -M. Baribeau +3
In a semiconductor heterostructure with type II energy band alignment, the spatial separation between electrons and holes slows down their radiative recombination. With increasing…
Unusual polarization patterns in flat epitaxial ferroelectric nanoparticles
Ivan I. Naumov, Alexander M. Bratkovsky
Interest in epitaxial ferroelectric nanoislands was growing rapidly in recent years driven by their potential for devices, especially ultradense memories. Recent advances in the "b…
Continuous theory of ferroelectric states in ultrathin films with real electrodes
A. M. Bratkovsky, A. P. Levanyuk
According to a continuous medium theory, in very thin ferroelectric films with real metallic electrodes (or dead layers near the electrodes) the domain structure reduces to sinusoi…
Modulation of Negative Index Metamaterials in the Near-IR Range
Evgenia Kim, Wei Wu, Ekaterina Ponizovskaya +5
Optical modulation of the effective refractive properties of a "fishnet" metamaterial with a Ag/Si/Ag heterostructure is demonstrated in the near-IR range and the associated fast d…
Path to finding the critical thickness for memory in thin ferroelectric films
A. M. Bratkovsky, A. P. Levanyuk
The finite screening length by real metallic electrodes, albeit very small (<1A), results in finite depolarizing field that tends to split the film into domains. In very thin ferro…
Optical Metamaterials at Near and Mid IR Range Fabricated by Nanoimprint Lithography
W. Wu, E. Kim, E. Ponizovskaya +10
Two types of optical metamaterials operating at near-IR and mid-IR frequencies, respectively, have been designed, fabricated by nanoimprint lithography (NIL), and characterized by…
Depolarizing field and "real" hysteresis loops in nanometer-scale ferroelectric films
A. M. Bratkovsky, A. P. Levanyuk
We give detailed analysis of the effect of depolarizing field in nanometer-size ferroelectric capacitors studied by Kim et al. [Phys. Rev. Lett. 95, 237602 (2005)]. We calculate a…
Polydomain ferroelectricity in very thin films [D.J. Kim et al., Phys.Rev.Lett. 95, 237602 (2005)]
A. M. Bratkovsky, A. P. Levanyuk
T.W. Noh and his group (Kim et al.: PRL, 2005) have recently published a seminal experimental study of very thin ferroelectric (FE) BaTiO3 capacitors. They found an evidence that a…
Comment on 'Hysteresis, Switching, and Negative Differential Resistance in Molecular Junctions: a Polaron Model', by M. Galperin, M.A. Ratner, and A. Nitzan, Nano Lett. 5, 125 (2005)
A. S. Alexandrov, A. M. Bratkovsky
It is shown that the ``hysteresis'' in a polaron model of electron transport through the molecule found by M.Galperin et al. [Nano Lett. 5, 125 (2005)] is an artefact of their ``me…
Phase transitions and ferroelectricity in very thin films: single- versus multidomain state
A. M. Bratkovsky, A. P. Levanyuk
We discuss ferroelectric phase transitions into single- and multidomain states in very thin films using continuous theory. It is shown that in nearly cubic ferroelectrics the domai…
Spin accumulation in degenerate semiconductors near modified Schottky contact with ferromagnets
V. V. Osipov, A. M. Bratkovsky
We study spin transport in forward and reverse biased junctions between a ferromagnetic metal and a degenerate semiconductor with a delta-doped layer near the interface at relative…
Strong effect of surfaces on resolution limit of negative-index "superlens"
A. M. Bratkovsky, A. Cano, A. P. Levanyuk
We show that subwavelength imaging by negative index materials (NIM), related to their "soft" electromagnetic response, is very (and non trivially) sensitive to the surface propert…
Smearing of phase transition due to surface effect in ferroelectric nanostructures
A. M. Bratkovsky, A. P. Levanyuk
The boundary conditions, customarily used in the Landau-type approach to ferroelectric thin films and nanostructures, have to be modified to take into account that a surface of a f…
Highly polarized injection luminescence in forward-biased ferromagnetic-semiconductor junctions at low spin polarization of current
A. M. Bratkovsky, V. V. Osipov
We consider electron tunneling from a nonmagnetic -type semiconductor (-S) into a ferromagnet (FM) through a very thin forward-biased Schottky barrier resulting in efficient…
Smearing of phase transition due to a surface effect or a bulk inhomogeneity in ferroelectric nanostructures
A. M. Bratkovsky, A. P. Levanyuk
The boundary conditions, customarily used in the Landau-type approach to ferroelectric thin films and nanostructures, have to be modified to take into account that a surface of a f…
A class of spin injection-precession ultrafast nanodevices
V. V. Osipov, A. M. Bratkovsky
Spin valve ultrafast spin injection devices are described: an amplifier, a frequency multiplier, and a square-law detector. Their operation is based on injection of spin polarized…
High-frequency spin valve effect in ferromagnet-semiconductor-ferromagnet structure based on precession of injected spins
A. M. Bratkovsky, V. V. Osipov
New mechanism of magnetoresistance, based on tunneling-emission of spin polarized electrons from ferromagnets (FM) into semiconductors (S) and precession of electron spin in the se…
Spin extraction from a non-magnetic semiconductor
A. M. Bratkovsky, V. V. Osipov
New efficient mechanism of obtaining spin polarization in_nonmagnetic_ semiconductors at arbitrary temperutures is described. The effect appears during tunneling of electrons from…
Efficient nonlinear room-temperature spin injection from ferromagnets into semiconductors through a modified Schottky barrier
V. V. Osipov, A. M. Bratkovsky
We suggest a consistent microscopic theory of spin injection from a ferromagnet (FM) into a semiconductor (S). It describes tunneling and emission of electrons through modified FM-…
Orientational dependence of current through molecular films
P. E. Kornilovitch, A. M. Bratkovsky
We study the current through molecular films as a function of orientation of the molecules in the film with respect to electrodes. It may change by more than an order of magnitude,…