Related papers: Imaging a Single-Electron Quantum Dot
The scanning metallic tip of a scanning force microscope was coupled capacitively to electrons confined in a lithographically defined gate-tunable quantum dot at a temperature of 300 mK. Single electrons were made to hop on or off the dot…
Motivated by the recent experiments by the Westervelt group using a mobile tip to probe the electronic state of quantum dots formed on a segmented nanowire, we study the shifts in Coulomb blockade peak positions as a function of the spatial…
Nanowire heterostructures define high-quality few-electron quantum dots for nanoelectronics, spintronics and quantum information processing. We use a cooled scanning probe microscope (SPM) to image and control an InAs quantum dot in an…
Strong confinement of charges in few electron systems such as in atoms, molecules and quantum dots leads to a spectrum of discrete energy levels that are often shared by several degenerate quantum states. Since the electronic structure is…
We report the fabrication and electrical characterization of a single electron transistor in a modulation doped silicon/silicon-germanium heterostructure. The quantum dot is fabricated by electron beam lithography and subsequent reactive…
We review the mechanisms of low-temperature electron transport across a quantum dot weakly coupled to two conducting leads. Conduction in this case is controlled by the interaction between electrons. At temperatures moderately lower than…
We study the interplay between Coulomb blockade and the Kondo effect in quantum dots. We use a self-consistent scheme which describes mesoscopic devices in terms of a collective phase variable (slave rotor) and quasiparticle degrees of…
Images of electron flow through a two-dimensional electron gas from a quantum point contact (QPC) can be obtained at liquid He temperatures using scanning probe microscopy (SPM). A negatively charged SPM tip depletes the electron gas…
We find an analytical expression for the conductance of a single electron transistor in the regime when temperature, level spacing, and charging energy of a grain are all of the same order. We consider the model of equidistant energy levels…
We show how a scanning probe microscope (SPM) can be used to image electron flow through InAs nanowires, elucidating the physics of nanowire devices on a local scale. A charged SPM tip is used as a movable gate. Images of nanowire…
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…
The temperature dependence of Coulomb blockade peak height correlation is used to investigate how adding electrons to a quantum dot alters or "scrambles" its electronic spectrum. Deviations from finite-temperature random matrix theory with…
We study conductance through a quantum dot under Coulomb blockade conditions in the presence of an external periodic perturbation. The stationary state is determined by the balance between the heating of the dot electrons by the…
Single electron charging in an individual InAs quantum dot was observed by electrostatic force measurements with an atomic force microscope (AFM). The resonant frequency shift and the dissipated energy of an oscillating AFM cantilever were…
We present Coulomb Blockade measurements of two few-electron quantum dots in series which are configured such that the electrochemical potential of one of the two dots is aligned with spin-selective leads. The charge transfer through the…
We show that two electrons confined in a square semiconductor quantum dot have two isolated low-lying energy eigenstates, which have the potential to form the basis of scalable computing elements (qubits). Initialisation, one-qubit and…
We report transport measurements on a semiconductor quantum dot with a small number of confined electrons. In the Coulomb blockade regime, conduction is dominated by cotunneling processes. These can be either elastic or inelastic, depending…
Recent innovations in fabricating nanoscale confined spin systems have enabled investigation of fundamental quantum correlations between single quanta of photons and matter states. Realization of quantum state transfer from photon…
Solid-state devices can be fabricated at the atomic scale, with applications ranging from classical logic to current standards and quantum technologies. While it is very desirable to probe these devices and the quantum states they host at…
We demonstrate local detection of the electron temperature in a two-dimensionalmicrodomain using a quantum dot. Our method relies on the observation that a temperature bias across the dot changes the functional form of Coulomb-blockade…