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  • 1. Gorini, C.
    et al.
    Schwab, P.
    Raimondi, R.
    Shelankov, Andrey
    Umeå University, Faculty of Science and Technology, Department of Physics. 5 Ioffe Physicotechnical Institute, RAS, St. Petersburg, Russia.
    Non-Abelian gauge fields in the gradient expansion: generalized Boltzmann and Eilenberger equations2010In: Physical Review B Condensed Matter, ISSN 0163-1829, E-ISSN 1095-3795, Vol. 82, no 19, 195316Article in journal (Refereed)
    Abstract [en]

    We present a microscopic derivation of the generalized Boltzmann and Eilenberger equations in the presence of non-Abelian gauges for the case of a nonrelativistic disordered Fermi gas. A unified and symmetric treatment of the charge [U(1)] and spin [SU(2)] degrees of freedom is achieved. Within this framework, just as the U(1) Lorentz force generates the Hall effect, so does its SU(2)counterpart gives rise to the spin Hall effect. Considering elastic and spin-independent disorder we obtain diffusion equations for charge and spin densities and show how the interplay between an in-plane magnetic field and a time-dependent Rashba term generates in-plane charge currents.

  • 2. Gurevich, V.L.
    et al.
    Kozub, V.I.
    Shelankov, Andrei
    Umeå University, Faculty of Science and Technology, Physics.
    Thermoelectric effect in superconducting nanostructures2006In: European Physics Journal B, Vol. 51, 285- p.Article in journal (Refereed)
  • 3. Kvyatkovskii, E.
    et al.
    Zacharova, I.B.
    Shelankov, Andrei
    Umeå University, Faculty of Science and Technology, Physics.
    Makarova, Tatiana
    Umeå University, Faculty of Science and Technology, Physics.
    Spin-transfer mechanism of ferromagnetism in polymerized fullerenes: Ab initio calculations2005In: Physical Review B, Vol. 72, no 21, 214426- p.Article in journal (Refereed)
  • 4. Kvyatkovskii, O.E.
    et al.
    Makarova, Tatiana
    Umeå University, Faculty of Science and Technology, Physics.
    Zacharova, I.B.
    Shelankov, Andrei
    Umeå University, Faculty of Science and Technology, Physics.
    Quantum-chemical ab initio calculations of the structure, energetics, and electronic properies of the calculations C60 neutral and charged dimers2004In: AIP Conference Proceedings vol. 723, 2004, 385- p.Conference paper (Refereed)
  • 5. Kvyatkovskii, Oleg E
    et al.
    Zacharova, Irina B
    Shelankov, Andrei
    Umeå University, Faculty of Science and Technology, Department of Physics. A.F. Ioffe Physico‐Technical Institute of the RAS , St. Petersburg, Russia .
    Makarova, Tatiana
    Umeå University, Faculty of Science and Technology, Department of Physics. A.F. Ioffe Physico‐Technical Institute of the RAS , St. Petersburg, Russia .
    Magnetic transition in the polymerized fullerene matrix2006In: Fullerenes, Nanotubes and Carbon Nanostructures vol. 14, issue 2&3: Proceedings of the International Workshop on Fullerenes and Atomic Clusters 2005 (IWFAC2005), St. Petersburg, Taylor & Francis, 2006, Vol. 2-3, 373-380 p.Conference paper (Refereed)
    Abstract [en]

    A mechanism of the ferromagnetism in the polymerized fullerene phase is proposed. We show that non‐magnetic defects and impurities give rise to a magnetic transition in the polymerized fullerene matrix. In our model, C60 molecules acquire spin and charge and become magnetically active due to the spin and charge transfer from non‐magnetic dopants. The interaction between magnetic moments of the arising paramagnetic species (C60 ± ions or C60 R radical adducts) dispersed in the polymeric network is inspected by using ab initio Hartree‐Fock and B3LYP hybrid density functional methods. It is revealed that the interaction is ferromagnetic and large enough for creating the high‐T c magnetism.

  • 6. Kvyatkovskii, Oleg E
    et al.
    Zakharova, Irina B
    Shelankov, Andrei L
    Umeå University, Faculty of Science and Technology, Department of Physics. A. F. Ioffe Physico‐Technical Institute of the RAS , St. Petersburg, Russia .
    Makarova, Tatiana L
    Umeå University, Faculty of Science and Technology, Department of Physics. A. F. Ioffe Physico‐Technical Institute of the RAS , St. Petersburg, Russia .
    Magnetic properties of polymerized fullerene doped with hydrogen, fluorine and oxygen2006In: Fullerenes, nanotubes, and carbon nanostructures (Print), ISSN 1536-383X, E-ISSN 1536-4046, Vol. 14, no 2-3, 385-389 p.Article in journal (Refereed)
    Abstract [en]

    We have presented recently a mechanism of ferromagnetism in polymeric fullerene phases based on spin and charge transfer from nonmagnetic donor or acceptor centers into fullerene molecules. In this work, the interaction between magnetic moments of the paramagnetic C60R radical adducts (R = H, F, OH) dispersed in the 2D polymeric network is examined by using UB3LYP hybrid density functional method at 3-21G level. The results show that the interaction is ferromagnetic, strong and long-range.

  • 7.
    Makarova, Tatiana L.
    et al.
    Umeå University, Faculty of Science and Technology, Department of Physics.
    Kvyatkovskii, Oleg E.
    Zakharova, Irina B.
    Buga, Sergei G.
    Voklov, Aleksandr P.
    Shelankov, Andrei L.
    Umeå University, Faculty of Science and Technology, Department of Physics.
    Laser controlled magnetism in hydrogenated fullerene films2011In: Journal of Applied Physics, ISSN 0021-8979, E-ISSN 1089-7550, Vol. 109, no 8, 083941-7 p.Article in journal (Refereed)
    Abstract [en]

    Room temperature ferromagnetic-like behavior in fullerene photopolymerized films treated with monatomic hydrogen is reported. The hydrogen treatment controllably varies the paramagnetic spin concentration and laser induced polymerization transforms the paramagnetic phase to a ferromagnetic-like one. Excess laser irradiation destroys magnetic ordering, presumably due to structural changes, which was continuously monitored by Raman spectroscopy. We suggest an interpretation of the data based on first-principles density-functional spin-unrestricted calculations which show that the excess spin from mono-atomic hydrogen is delocalized within the host fullerene and the laser-induced polymerization promotes spin exchange interaction and spin alignment in the polymerized phase.

  • 8.
    Makarova, Tatiana L.
    et al.
    Umeå University, Faculty of Science and Technology, Department of Physics.
    Kvyatkovskii, Oleg E.
    Zakharova, Irina B.
    Buga, Sergei G.
    Volkov, Aleksandr P.
    Shelankov, Andrei L.
    Umeå University, Faculty of Science and Technology, Department of Physics.
    Response to "Comment on 'Laser controlled magnetism in hydrogenated fullerene films'" [J. Appl. Phys. 113, 036101 (2013)]2013In: Journal of Applied Physics, ISSN 0021-8979, E-ISSN 1089-7550, Vol. 113, no 3, 036102- p.Article in journal (Other academic)
  • 9.
    Makarova, Tatiana L.
    et al.
    Umeå University, Faculty of Science and Technology, Department of Physics.
    Shelankov, Aandrei L.
    Umeå University, Faculty of Science and Technology, Department of Physics.
    Lyubchik, Svetlana B.
    Serenkov, Igor T.
    Sakharov, Vladimir I.
    Induced Ferromagnetism in Helium-Bombarded Graphite2012In: Journal of Nanoscience and Nanotechnology, ISSN 1533-4880, Vol. 12, no 6, 5051-5053 p.Article in journal (Refereed)
    Abstract [en]

    Irradiation with helium ions is an effective method for triggering ferromagnetism in graphite. Chemical inertness of helium suggests that local magnetic moment formation is determined solely by the intrinsic carbon defects created during the target damage. Interacting moments are located in two places: in the vicinity of the sample surface and near the point of maximum defect generation.

  • 10.
    Makarova, Tatiana. L.
    et al.
    Umeå University, Faculty of Science and Technology, Department of Physics.
    Shelankov, Andlei L.
    Umeå University, Faculty of Science and Technology, Department of Physics.
    Serenkov, I. T.
    Sakharov, V. I.
    Boukhwalov, D. W.
    Anisotropic magnetism of graphite irradiated with medium-energy hydrogen and helium ions2011In: Physical Review B Condensed Matter, ISSN 0163-1829, E-ISSN 1095-3795, Vol. 83, no 8, 085417-8 pages p.Article in journal (Refereed)
    Abstract [en]

    We have studied the changes in the magnetic behavior of highly oriented pyrolytic graphite (HOPG) samples subjected to medium-energy proton and helium irradiation. The variations of the ferromagneticlike magnetization curves with the irradiation dose have been studied for two configurations: magnetic fields parallel and perpendicular to graphitic planes. For high irradiation doses, the values of magnetization at saturation are close for both geometries. At low irradiation fluences an orientationally dependent magnetic response is obtained. Directional dependence of magnetization indicates that the magnetism in irradiated graphite is triggered by vertically aligned intrinsic carbon defects induced by irradiation. This physical picture has been verified by the observation of a local stray field near linear defects by means of magnetic force microscopy. Similar results obtained with hydrogen and helium ions confirm that the chemical nature of projectiles is not crucial for formation of ferromagnetic order in oriented graphite. The dependence of induced magnetic moment versus irradiation dose shows a maximum; the optimal dose is an order of magnitude less for helium ions than for protons, being in line with simulations showing that He+ generates 8 times more defects than H+. Raman studies indicate that the degradation of magnetic ordering at large irradiation doses occurs much earlier than graphite amorphization but coincides with the destruction of graphene sheet stacking.

  • 11.
    Makarova, Tatiana L.
    et al.
    Umeå University, Faculty of Science and Technology, Department of Physics.
    Zakharova, I. B.
    State Polytechnical University, St Petersburg, Russia.
    Kvyatkovskii, O. E.
    Ioffe Physico-Technical Institute, St Petersburg, Russia.
    Buga, S. G.
    Technological Institute for Superhard and Novel Carbon Materials, Troitsk, Russia.
    Volkov, A. P.
    Technological Institute for Superhard and Novel Carbon Materials, Troitsk, Russia.
    Shelankov, Andrei L.
    Umeå University, Faculty of Science and Technology, Department of Physics.
    Experimental realization of high spin states in dilutely hydrogenated fullerenes2009In: Physica status solidi. B, Basic research, ISSN 0370-1972, E-ISSN 1521-3951, Vol. 246, no 11-12, 2778-2781 p.Article in journal (Refereed)
    Abstract [en]

    A novel method for preparing dilutely hydrogenated fullerenes H:C60 is presented. DFT calculations of the Raman spectra at the B3LYP/3-21G level are compared with the experimental data. Under the laser treatment these phases form a rich variety of dimeric and polymeric structures, quite in contrast to pristine C60 which forms dimers and polymers bonded through the [2 + 2] addition, and in contrast to heavily hydrogenated fullerenes which do not polymerize at all. Dilutely hydrogenated fullerenes polymerize differently, forming both double bonded structures and single bonded dimers. We have shown that dilute hydrogenation of C60 creates large amount of unpaired spins which disappear due to the formation of diamagnetic single bonded dimers.

  • 12.
    Makarova, Tatiana
    et al.
    Umeå University, Faculty of Science and Technology, Department of Physics.
    Shelankov, Andlei L.
    Umeå University, Faculty of Science and Technology, Department of Physics.
    Serenkov, Igor T.
    Sakharov, Vladimir I.
    Magnetism in graphite induced by irradiation of hydrogen and helium atoms: a comparative study2010In: Physica status solidi. B, Basic research, ISSN 0370-1972, E-ISSN 1521-3951, Vol. 247, no 11-12, 2988-2991 p.Article in journal (Refereed)
    Abstract [en]

    To identify the origin of defect-induced magnetism in ion-irradiated graphite, a comparative study of samples of graphite irradiated with hydrogen H+ and helium He+ ions is performed. Directionally dependent magnetic properties, atomic/magnetic force microscopy studies suggest that the induced magnetic moments are located along the vertically aligned grain boundaries. Compared to the case of the hydrogen ion irradiation, the optimal helium irradiation dose is an order of magnitude lower. From this we conclude that the hydrogen chemistry is essentially irrelevant, and the ferromagnetic-like response of the irradiated graphite is due to structural defects regardless of their origin.

  • 13.
    Ozana, Marek
    et al.
    Umeå University, Faculty of Science and Technology, Department of Physics.
    Shelankov, Andrei
    Umeå University, Faculty of Science and Technology, Department of Physics.
    Quasiclassical theory of superconductivity: Interfering paths2002In: Physical Review B. Condensed Matter and Materials Physics, ISSN 1098-0121, E-ISSN 1550-235X, Vol. 65, no 1, 014510- p.Article in journal (Refereed)
    Abstract [en]

    We apply the method of a two-point quasiclassical Green's function to geometries where the trajectories include intefering paths and loops. For a system of two superconducting layers separated by a partially transparent interface, corrections to the quasiclassical solutions for the Green's function are explicitly found as well as the deviation from the normalization condition.

  • 14.
    Ozana, Marek
    et al.
    Umeå University, Faculty of Science and Technology, Department of Physics.
    Shelankov, Andrei
    Umeå University, Faculty of Science and Technology, Department of Physics.
    Superconductivity in multiple interface geometry: Applicability of quasiclassical theory2001In: Journal of Low Temperature Physics, ISSN 0022-2291, E-ISSN 1573-7357, Vol. 124, no 1-2, 223-243 p.Article in journal (Refereed)
    Abstract [en]

    The method of two-point quasiclassical Green's function is reviewed and its applicability for description of multiple reflections/transmissions in layered structures is discussed. The Green's function of a sandwich built of super-conducting layers with a semi-transparent interface is found with the help of recently suggested quasiclassical method [A. Shelankov and M. Ozana, Phys. Rev. B 61. 7077 (2000)], as well as exactly, from thc Gor'kov equation. By the comparison of the results of the two approaches, thc validity of the quasiclassical method for thc description of real (non-integrable) systems is confirmed.

  • 15.
    Ozana, Marek
    et al.
    Umeå University, Faculty of Science and Technology, Department of Physics.
    Shelankov, Andrei L
    Squeezed states of a particle in magnetic field1998In: Physics of the solid state, ISSN 1063-7834, E-ISSN 1090-6460, Vol. 40, no 8, 1276-1282 p.Article in journal (Refereed)
    Abstract [en]

    For a charged particle in a homogeneous magnetic field, we construct stationary squeezed states which are eigenfunctions of the Hamiltonian and the non-Hermitian operator (X) over cap(Phi) = (X) over cap cos Phi + (Y) over cap sin Phi, (X) over cap and (Y) over cap being the coordinates of the Larmor circle center and Phi is a complex parameter. In the family of the squeezed states, the quantum uncertainty in the Larmor circle position is minimal. The wave functions of the squeezed states in the coordinate representation are found and their properties are discussed. Besides, for arbitrary gauge of the vector potential we derive the symmetry operators of translations and rotations.

  • 16.
    Ozana, Marek
    et al.
    Umeå University, Faculty of Science and Technology, Department of Physics.
    Shelankov, Andrei
    Umeå University, Faculty of Science and Technology, Department of Physics.
    Tobiska, J
    Umeå University, Faculty of Science and Technology, Department of Physics.
    Bogoliubov-de Gennes versus quasiclassical description of Josephson layered structures2002In: Physical Review B. Condensed Matter and Materials Physics, ISSN 1098-0121, E-ISSN 1550-235X, Vol. 66, no 5, 054508- p.Article in journal (Refereed)
    Abstract [en]

    The applicability of the quasiclassical theory of superconductivity in Josephson multilayer structures is analyzed. The quasiclassical approach is compared with the exact theory based on the Bogoliubov-de Gennes equation. The angle- and energy-resolved (coarse-grain) currents are calculated using both techniques. It is shown that the two approaches agree in SIS'IS" geometries after the coarse-grain averaging. A quantitative discrepancy, which exceeds the quasiclassical accuracy, is observed when three or more interfaces are present. The invalidity of the quasiclassical theory is attributed to the presence of closed trajectories formed by sequential reflections from the interfaces.

  • 17.
    Rammer, Jörgen
    et al.
    Umeå University, Faculty of Science and Technology, Department of Physics.
    Shelankov, Andrei
    Umeå University, Faculty of Science and Technology, Department of Physics.
    Counting quantum fluctuations of particle density2012In: Annalen der Physik, ISSN 0003-3804, E-ISSN 1521-3889, Vol. 524, no 3-4, 163-174 p.Article in journal (Refereed)
    Abstract [en]

    Methods of charge projectors using special gauge transformations for tagging particles are presented. Such engineering of a many-body wave function allows extracting information regarding properties of a physical system beyond average values. The method is first used to establish under which circumstances the properties of particle currents can be understood as discrete transfers of particles from one region to another. Next, the method is extended to show that in a tunnel junction coupled to a two-level system, the transmission of electrical noise causes decoherence and thereby a projective measurement of the two-level system as encoded by the amount of tunnelled charge. Finally the method is extended to deal with the exceptional circumstance where a measurement on a system with a large number of particles gives macroscopically distinguishable outcomes that are unpredictable, the observed interference pattern of interfering BEC's.

  • 18.
    Rammer, Jörgen
    et al.
    Umeå University, Faculty of Science and Technology, Department of Physics.
    Shelankov, Andrei L.
    Umeå University, Faculty of Science and Technology, Department of Physics.
    Wabnig, Joachim
    Umeå University, Faculty of Science and Technology, Department of Physics.
    Quantum measurement in the charge representation2004In: Physical Review B. Condensed Matter and Materials Physics, ISSN 1098-0121, E-ISSN 1550-235X, Vol. 70, 115327- p.Article in journal (Refereed)
    Abstract [en]

    Counting statistics of charge transfers in a point contact interacting with an arbitrary quantum system is studied. The theory for the charge specific density matrix is developed, allowing the evaluation of the probability of the outcome of any joint measurement of the state of the quantum system and the transferred charge. Applying the method of charge projectors, the master equation for the charge specific density matrix is derived in the tunneling Hamiltonian model of the point contact. As an example, the theory is applied to a quantum measurement of a two-state system: The evolution of the charge specific density matrix in the presence of Nyquist or Schottky noise is studied and the conditions for the realization of a projective measurement are established.

  • 19.
    Shelankov, Andrei
    et al.
    Umeå University, Faculty of Science and Technology, Department of Physics.
    Ozana, Marek
    Umeå University, Faculty of Science and Technology, Department of Physics.
    Quasiclassical theory of superconductivity: A multiple-interface geometry2000In: Physical Review B. Condensed Matter and Materials Physics, ISSN 1098-0121, E-ISSN 1550-235X, Vol. 61, no 10, 7077-7100 p.Article in journal (Refereed)
    Abstract [en]

    A method is suggested that allows one to study multiple coherent reflection/transmissions by partially transparent interfaces (e.g., in multilayer mesoscopic structures or grain boundaries in high T-c's), in the framework of the quasiclassical theory of superconductivity. It is argued that in the presence of interfaces, a straight-line trajectory transforms to a simple connected one-dimensional tree (graph) with knots, i.e., the points where the interface scattering events occur and pieces of the trajectories are coupled. For the two-component trajectory "wave function" which factorizes the Gor'kov matrix Green's function, a linear boundary condition on the knot is formulated for an arbitrary interface, specular or diffusive (in the many channel model). From the new boundary condition, we derive (i) the excitation scattering amplitude for the multichannel Andreev/ordinary reflection/transmission processes; (ii) the boundary conditions for the Riccati equation; (iii) the transfer matrix which couples the trajectory Green's function before and after the interface scattering. To show the usage of the method, the cases of a him separated from a hulk superconductor by a partially transparent interface, and a SIS' sandwich with finite thickness layers, are considered. The electric current response to the vector potential (the superfluid density rho(s)) with the pi phase difference in S and S' is calculated for the sandwich. It is shown that the model is very sensitive to imperfection of the SS' interface: the low temperature response being paramagnetic (rho(s) < 0) in the ideal system case, changes its sign and becomes diamagnetic (rho(s) > 0) when the probability of reflection is as low as a few percent.

  • 20.
    Shelankov, Andrei
    et al.
    Umeå University, Faculty of Science and Technology, Department of Physics.
    Rammer, Jörgen
    Umeå University, Faculty of Science and Technology, Department of Physics.
    Charge transfer counting statistics revisited2003In: Europhysics letters, ISSN 0295-5075, E-ISSN 1286-4854, Vol. 63, no 4, 485-491 p.Article in journal (Refereed)
    Abstract [en]

    Charge transfer statistics of quantum particles is obtained by analysing the time evolution of the many-body wave function. Exploiting properly chosen gauge transformations, we construct the probabilities for transfers of a discrete number of particles. Generally, the derived formula for counting statistics differs from the one previously obtained by Levitov et al. (J. Math. Phys., 37 (1996) 4845). The two formulae agree only if the initial state is prohibited from being a superposition of different charge states. Their difference is illustrated for cases of a single particle and a tunnel junction, and the role of charge coherence is demonstrated

  • 21.
    Shelankov, Andrei
    et al.
    Umeå University, Faculty of Science and Technology, Department of Physics.
    Rammer, Jörgen
    Umeå University, Faculty of Science and Technology, Department of Physics.
    Counting statistics of interfering Bose-Einstein condensates2008In: Europhysics letters, ISSN 0295-5075, E-ISSN 1286-4854, Vol. 83, no 6, 6002- p.Article in journal (Refereed)
    Abstract [en]

    A method is presented that is able to predict the probability of outcomes of snapshot measurements, such as the images of the instantaneous particle density distribution in a quantum many-body system. It is shown that a gauge-like transformation of the phase of the many-body wave function allows one to construct a probability generating functional, the Fourier transform of which with respect to the “gauge” field returns the joint probability distribution to detect any given number of particles at various locations. The method is applied to the problem of interference of two independent clouds of Bose-Einstein condensates, where the initially separated clouds with fixed boson numbers expand and the density profile image of the overlapping clouds is registered. In the limit of large particle numbers, the probability to observe a particular image of the density profile is shown to be given by a sum of partial probability distributions, each of which corresponds to a noisy image of interference of two matter waves with definite phase difference. In agreement with earlier theoretical arguments, interference fringes are, therefore, expected in any single shot measurement, the fringe pattern randomly varying from run to run. These results conform to the physical picture where the Bose-Einstein clouds are in spontaneously symmetry broken states, the hidden phases of which are revealed by the density profile measurement via the position of the interference fringes.

  • 22.
    Wabnig, Joachim
    et al.
    Umeå University, Faculty of Science and Technology, Department of Physics.
    Khomitsky, D.V.
    Umeå University, Faculty of Science and Technology, Department of Physics.
    Rammer, Jörgen
    Umeå University, Faculty of Science and Technology, Department of Physics.
    Shelankov, Andrei
    Umeå University, Faculty of Science and Technology, Department of Physics.
    Statistics of charge transfer in a tunnel junction coupled to an oscillator2005In: Physical Review B Condensed Matter, ISSN 0163-1829, E-ISSN 1095-3795, Physical Review B, Vol. 72, no 16, 165347- p.Article in journal (Refereed)
    Abstract [en]

    The charge transfer statistics of a tunnel junction coupled to a quantum object is studied using the charge projection technique. The joint dynamics of the quantum object and the number of charges transferred through the junction is described by the charge specific density matrix. The method allows evaluating the joint probability distribution of the state of the quantum object and the charge state of the junction. The statistical properties of the junction current are derived from the charge transfer statistics using the master equation for the charge specific density matrix. The theory is applied to a nanoelectromechanical system, and the influence on the average current and the current noise of the junction is obtained for coupling to a harmonic oscillator.

  • 23.
    Wabnig, Joachim
    et al.
    Umeå University, Faculty of Science and Technology, Department of Physics.
    Rammer, Jörgen
    Umeå University, Faculty of Science and Technology, Department of Physics.
    Shelankov, Andrei L.
    Umeå University, Faculty of Science and Technology, Department of Physics.
    Noise spectrum of a tunnel junction coupled to a nanomechanical oscillator2007In: Physical Review B. Condensed Matter and Materials Physics, ISSN 1098-0121, E-ISSN 1550-235X, Physical Review B, Vol. 75, no 20, 205319-13 p p.Article in journal (Refereed)
    Abstract [en]

    A nanomechanical resonator coupled to a tunnel junction is studied. The oscillator modulates the transmission of the junction, changing the current and the noise spectrum. The influence of the oscillator on the noise spectrum of the junction is investigated, and the noise spectrum is obtained for arbitrary frequencies, temperatures, and bias voltages. We find that the noise spectrum consists of a noise floor and a peaked structure with peaks at zero frequency, the oscillator frequency, and twice the oscillator frequency. The influence of the oscillator vanishes if the bias voltage of the junction is lower than the oscillator frequency. We demonstrate that the peak at the oscillator frequency can be used to determine the oscillator occupation number, showing that the current noise in the junction functions as a thermometer for the oscillator.

1 - 23 of 23
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