Magnetic Field Effects on Anisotropic Parabolic Quantum Dots

Natori, Akiko; Sugimoto, Yuichiro; Fujito, Masamichi

doi:10.1143/jjap.36.3960

Cited by 17 publications

(6 citation statements)

References 22 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The properties of the MDD and electronic states under higher magnetic field have been studied experimentally 28 and theoretically. 10,29…”

Section: Electronic States In Quantum Dotsmentioning

confidence: 99%

Electronic States and Transport Phenomena in Quantum Dot Systems

Eto¹

2001

Jpn. J. Appl. Phys.

View full text Add to dashboard Cite

Electronic states and transport phenomena in semiconductor quantum dots are studied theoretically. Taking account of the electron-electron Coulomb interaction by the exact diagonalization method, the ground state and low-lying excited states are calculated as functions of magnetic field. Using the obtained many-body states, we discuss the temperature dependence of the conductance peaks in the Coulomb oscillation. In the Coulomb blockade region, elastic and inelastic cotunneling currents are evaluated under finite bias voltages. The cotunneling conductance is markedly enhanced by the Kondo effect. In coupled quantum dots, molecular orbitals and electronic correlation influence the transport properties.

show abstract

“…The properties of the MDD and electronic states under higher magnetic field have been studied experimentally 28 and theoretically. 10,29…”

Section: Electronic States In Quantum Dotsmentioning

confidence: 99%

Electronic States and Transport Phenomena in Quantum Dot Systems

Eto¹

2001

Jpn. J. Appl. Phys.

View full text Add to dashboard Cite

show abstract

“…[11][12][13] This theory was also applied to evaluate the addition spectra in elliptical quantum dots. 14 The addition spectra of elliptical dots have been studied with Hartree-Fock method 15 as well. The effect of pinning of the Wigner molecule by a Gaussian impurity perturbation in an isotropic confinement potential was recently studied by the quantum Monte Carlo approach.…”

Section: Introductionmentioning

confidence: 99%

Anisotropic quantum dots: Correspondence between quantum and classical Wigner molecules, parity symmetry, and broken-symmetry states

et al. 2004

View full text Add to dashboard Cite

We study electron systems confined in anisotropic quantum dots at high magnetic fields using the configuration-interaction scheme with a multicenter basis of single-electron functions centered around different sites. Elliptical, triangular, and square quantum dots are investigated. We study the relation between the quantum and classical charge density and conclude that at high magnetic field the quantum charge density reproduces all the equivalent lowest-energy configurations of classical point charges. Quantum systems with a classical counterpart of a unique lowest-energy configuration exhibit a smooth convergence of the charge density to the classical limit at high magnetic field. In quantum systems with several equivalent classical configurations the magnetic field induces discontinuous transformations of the ground-state symmetry associated with crossings of the corresponding few-electron energy levels. A linear combination of states with the crossing levels yields a semiclassical charge density with a broken symmetry. At the magnetic field corresponding to the level crossing this combination is an exact eigenstate of the Hamiltonian. For circular dots the present findings give an additional insight into the properties of the magic-angular-momenta states and into the physics behind the broken-symmetry mean-field solutions.

show abstract

“…One should note that this type of QDO degeneracy has the potential to cause a transition of the ground-state spin phase. 10,12,14,15) For conventional 2D-QDs under the application of magnetic field, this phase transition between spin singlet (lower spin multiplicity) and spin triplet (higher spin multiplicity) has been clearly observed. 2) Therefore, we studied a possible spin-phase transition caused by the interelectron interaction, and calculated the total spin S as a function of the applied magnetic field.…”

Section: Introductionmentioning

confidence: 98%

“…Thereafter, focusing on the controllability of the electrons confined in the 2D-QDs, numerous works have been carried out experimentally as well as theoretically. [8][9][10][11][12][13][14][15][16] In addition to these 2D-QDs, the self-organized technique produces a different type of QD, namely, the three-dimensional spherical quantum dot (3D-SPQD). 17) These materials have rapidly attracted much interest because of their wide range of possible applications.…”

Section: Introductionmentioning

confidence: 99%

“…The Hartree-Fock (HF) treatment has been widely accepted for the study of the ground state for many electrons confined in the 2D-QDs. [10][11][12][13][14] In contrast, for 3D-SPQDs, it is necessary to employ a novel method beyond the HF approach, in order to constrain the total orbital angular momentum L. Both L 2 and L z are good quantum numbers for the 3D-SPQDs under the zero magnetic field, while the single Slater determinant (SSD) which is the solution of the HF method is not generally an eigenstate of the operator L L 2 . Consequently, in our last work, 18) we extended the unrestricted Hartree-Fock (exUHF) method in which the total orbital angular momentum L and its z component L z are conserved during the selfconsistent-field (scf) procedure.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

New Shell Structures and Their Ground Electronic States in Spherical Quantum Dots (II) under Magnetic Field

Asari

Takeda

Tamura

2005

Jpn. J. Appl. Phys.

View full text Add to dashboard Cite

We theoretically studied the electronic structure of the three-dimensional spherical parabolic quantum dot (3D-SPQD) under a magnetic field. We obtained the quantum dot orbitals (QDOs) and determined the ground state by using the extended UHF approach where the expectation values of the z component of the total orbital angular momentum <\hatL z > are conserved during the scf-procedure. The single-electron treatment predicts that the applied magnetic field (B) creates k-th new shells at the magnetic field of B k =k(k+2)/(k+1)ω0 with the shell-energy interval of \hbarω0/(k+1), where ω0(=\hbar/m * l 0 2) is the characteristic frequency originating from the spherical parabolic confinement potential. These shells are formed by the level crossing among multiple QDOs. The interelectron interaction breaks the simple level crossing but causes complicated dependences among the total energy, the chemical potential and their differences (magic numbers) with the magnetic field or the number of confinement electrons. The ground state having a higher spin multiplicity is theoretically predicted on the basis of the quasi-degeneracies of the QDOs around these shells.

show abstract

Magnetic Field Effects on Anisotropic Parabolic Quantum Dots

Cited by 17 publications

References 22 publications

Electronic States and Transport Phenomena in Quantum Dot Systems

Electronic States and Transport Phenomena in Quantum Dot Systems

Anisotropic quantum dots: Correspondence between quantum and classical Wigner molecules, parity symmetry, and broken-symmetry states

New Shell Structures and Their Ground Electronic States in Spherical Quantum Dots (II) under Magnetic Field

Contact Info

Product

Resources

About