Related papers: Quantum Mott transition in a silicon quantum dot
We explore the quantum transmission through open oval shaped quantum dots. The transmission spectra show periodic resonances and, depending on the geometry parameter, a strong suppression of the transmission for low energies. Applying a…
We describe the two-dimensional Mott transition in a Hubbard-like model with nearest neighbors interactions based on a recent solution to the Zamolodchikov tetrahedron equation, which extends the notion of integrability to two-dimensional…
We report electrical transport measurements through a semiconducting single-walled carbon nanotube (SWNT) with three additional top-gates. At low temperatures the system acts as a double quantum dot with large inter-dot tunnel coupling…
Spin qubits in semiconductor quantum dots represent a prominent family of solid-state qubits in the effort to build a quantum computer. They are formed when electrons or holes are confined in a static potential well in a semiconductor,…
A few electron double electrostatic lateral quantum dot can be transformed into a few electron triple quantum dot by applying a different combination of gate voltages. Quadruple points have been achieved at which all three dots are…
We have measured the low-temperature transport properties of a T-shaped quantum dot. Replicated oscillations superimposed on one-dimensional conductance steps are observed. These structures are consistent with electron phase-coherent length…
The Mott insulating state formed from bosons is ubiquitous in solid He-4, cold atom systems, Josephson junction networks and perhaps underdoped high-Tc superconductors. We predict that close to the quantum phase transition to the…
Quantum dots are fabricated in a Ga[Al]As-heterostructure by local oxidation with an atomic force microscope. This technique, in combination with top gate voltages, allows us to generate steep walls at the confining edges and small lateral…
Transport measurements at cryogenic temperatures through a few electron top gated quantum dot fabricated in a silicon/silicon-germanium heterostructure are reported. Variations in gate voltage induce a transition from an isolated dot toward…
In this paper initial experiments towards constructing simple quantum gates in a solid state material are presented. Instead of using specially tailored materials, the aim is to select a subset of randomly distributed ions in the material,…
Semiconductor-based quantum dot single-electron pumps are currently the most promising candidates for the direct realization of the emerging quantum standard of the ampere in the International System of Units. Here, we discuss a silicon…
We review the peculiarities of transport through a quantum dot caused by the spin transition in its ground state. Such transitions can be induced by a magnetic field. Tunneling of electrons between the dot and leads mixes the states…
We utilize a glass-like structural transition in order to induce a Mott metal-insulator transition in the quasi-two-dimensional organic charge-transfer salt $\kappa$-(BEDT-TTF)$_2$Cu[N(CN)$_2$]Br. In this material, the terminal ethylene…
To elucidate a quantum phase transition (QPT) in Bi_2Sr_{2-x}La_xCuO_{6+\delta}, we measure charge and heat transport properties at very low temperatures and examine the following characteristics for a wide range of doping: normal-state…
Successive quantum transitions in an intermediate regime are shown to exist between the superfluid and Mott insulating states for interacting bosonic atoms in one dimension with a trapping potential. These transitions, which are caused by…
We replace the established aluminium gates for the formation of quantum dots in silicon with gates made from palladium. We study the morphology of both aluminium and palladium gates with transmission electron microscopy. The native…
Double quantum dots are convenient solid-state platforms to encode quantum information. Two-electron spin states can be conveniently detected and manipulated using strong quantum selection rules based on the Pauli exclusion principle,…
Many-particle electron states in semiconductor quantum dots with carrier-mediated ferromagnetism are studied theoretically within the self-consistent Boltzmann equation formalism. Depending on the conditions, a quantum dot may contain there…
We study the magnetic field induced singlet/triplet transition for two electrons in vertically coupled quantum dots by exact diagonalization of the Coulomb interaction. We identify the different mechanisms occurring in the transition,…
High-temperature superconductivity emerges in the CuO$_2$ plane upon doping a Mott insulator. To ascertain the influence of Mott physics plus short-range correlations, we solve a three-band copper-oxide model in the charge-transfer regime…