English
Related papers

Related papers: Paramagnetic-diamagnetic interplay in quantum dots…

200 papers

Dipolar interaction between the magnetic moments of electrons is studied as a source for electron spin decay in quantum dots or arrays of quantum dots. This magnetic interaction will govern spin decay, after other sources, such as the…

Mesoscale and Nanoscale Physics · Physics 2009-11-11 Wolfgang Häusler , Peter Hänggi

We study a small spin-degenerate quantum dot with even number of electrons, weakly connected by point contacts to the metallic electrodes, and subject to an external magnetic field. If the Zeeman energy B is equal to the single-particle…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 M. Pustilnik , Y. Avishai , K. Kikoin

Using a classical and quantum mechanical analysis, we show that the magnetic field gives rise to dynamical symmetries of a three-dimensional axially symmetric two-electron quantum dot with a parabolic confinement. These symmetries manifest…

Condensed Matter · Physics 2009-11-07 N. S. Simonovic , R. G. Nazmitdinov

We study a thermally induced spin flip of an electron spin located in a semiconductor quantum dot. This interesting effect arises from an intriguing interplay between the Zeeman coupling to an external magnetic field and the hyperfine…

Mesoscale and Nanoscale Physics · Physics 2015-08-05 Moritz Fuchs , Felix Krauß , Daniel Hetterich , Björn Trauzettel

The correlation energies for two interacting electrons in a parabolic quantum dot are studied via a pseudo-perturbation recipe. It is shown that the central spike term, ($m^2-1/4)/r^2$, plays a distinctive role in determining the spectral…

Soft Condensed Matter · Physics 2007-05-23 Omar Mustafa

Electron spin relaxation in paramagnetic Ga(Mn)As quantum wells is studied via the fully microscopic kinetic spin Bloch equation approach where all the scatterings, such as the electron-impurity, electron-phonon, electron-electron Coulomb,…

Materials Science · Physics 2009-04-02 J. H. Jiang , Y. Zhou , T. Korn , C. Schüller , M. W. Wu

Magnetic properties of two and three-dimensional clusters of quantum dots are studied with exact diagonalization of a generalized Hubbard model. We study the weak coupling limit, where the electrons interact only within a quantum dot and…

Strongly Correlated Electrons · Physics 2009-11-13 J. -P. Nikkarila , M. Koskinen , M. Manninen

Orbital magnetism is studied for graphene flakes with various shapes and edge configurations using the tight-binding approximation. In the low-temperature regime where the thermal energy is much smaller than to the energy level spacing, the…

Mesoscale and Nanoscale Physics · Physics 2013-03-27 Yuya Ominato , Mikito Koshino

Observation of an anomalous temperature dependence of the spin susceptibility, along with a spin gap in NMR, in the quantum paramagnetic normal state of Iron Pnictides is a signature of an unusual metallic state. We argue that both these…

Strongly Correlated Electrons · Physics 2009-03-24 M. S. Laad , L. Craco

The equilibrium properties and interminiband transitions for Hartree-interacting two-dimensional electron gas in a one-dimensional chain of planar quantum rings subjected to a transverse homogeneous magnetic field are examined theoretically…

Mesoscale and Nanoscale Physics · Physics 2024-10-03 Armen Harutyunyan , Vram Mughnetsyan , Albert Kirakosyan , Vidar Gudmundsson

Magnetic correlations in the paramagnetic phase of CaFe2As2 (T_N=172 K) have been examined by means of inelastic neutron scattering from 180 K (~ 1.05 T_N) up to 300 K (~1.8 T_N). Despite the first-order nature of the magnetic ordering,…

Using a combination of single-crystal neutron scattering and reverse Monte Carlo refinements, we study the magnetic structure of paramagnetic MnO at a temperature (160\,K) substantially below the Curie-Weiss temperature…

We present a theoretical analysis of the nonlinear bias and temperature dependence of current-voltage characteristics of a spin-valve device which is formed by connecting a quantum dot to two ferromagnetic electrodes whose magnetic moments…

Condensed Matter · Physics 2015-06-25 Baigeng Wang , Jian Wang , Hong Guo

Within the mean-field theory, we investigate the magnetic properties of a charged spin-1 Bose gas in two dimension. In this system the diamagnetism competes with paramagnetism, where Lande-factor $g$ is introduced to describe the strength…

Statistical Mechanics · Physics 2015-06-17 Yingxue Chen , Jihong Qin , Qiang Gu

While it is known that the QCD vacuum in a magnetic background exhibits both diamagnetic and paramagnetic characteristics in the low-energy domain, a systematic investigation of the corresponding phases emerging in the pion-dominated regime…

High Energy Physics - Phenomenology · Physics 2021-05-26 Christoph P. Hofmann

Motivated by recent experiments, in which the Kondo effect has been observed for the first time in a double quantum-dot structure, we study electron transport through a system consisting of two ultrasmall, capacitively-coupled dots with…

Mesoscale and Nanoscale Physics · Physics 2009-10-31 Teemu Pohjola , Herbert Schoeller , Gerd Schön

Understanding the quantum dynamics of strongly interacting fermions is a problem relevant to diverse forms of matter, including high-temperature superconductors, neutron stars, and quark-gluon plasma. An appealing benchmark is offered by…

We present a theory of electronic properties of gated triangular graphene quantum dots with zigzag edges as a function of size and carrier density. We focus on electronic correlations, spin and geometrical effects using a combination of…

Mesoscale and Nanoscale Physics · Physics 2015-06-04 P. Potasz , A. D. Guclu , A. Wojs , P. Hawrylak

In order to understand the orbital and spin magnetization of a confined electronic system we analyze these ground state properties in the transition from a quantum dot to a quantum ring of finite thickness. The Coulomb interaction between…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 Gabriel Vasile , Vidar Gudmundsson , Andrei Manolescu

While the dynamics for three-dimensional axially symmetric two-electron quantum dots with parabolic confinement potentials is in general non-separable we have found an exact separability with three quantum numbers for specific values of the…

Mesoscale and Nanoscale Physics · Physics 2009-11-07 R. G. Nazmitdinov , N. S. Simonovic , Jan M. Rost