Related papers: Imaging a Coupled Quantum Dot - Quantum Point Cont…
We address the ultimate charge detection scheme with a quantum point contact. It is shown that a superposed input state is necessary to exploit the full sensitivity of a quantum point contact detector. The coherence of the input state…
In this letter, we have considered an electron in a coupled quantum dot system interacting with a detector represented by a point contact. We present a dynamical model for wave function collapse in the strong coupling to the detector limit.…
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…
As semiconductor device dimensions are reduced to the nanometer scale, effects of high defect density surfaces on the transport properties become important to the extent that the metallic character that prevails in large and highly doped…
We demonstrate electron redistribution caused by magnetic field on a single quantum dot measured by means of a quantum point contact as non-invasive detector. Our device which is fabricated by local anodic oxidation allows to control…
We describe an electrodynamic mechanism for coherent, quantum mechanical coupling between spacially separated quantum dots on a microchip. The technique is based on capacitive interactions between the electron charge and a superconducting…
Quantum point contacts (QPC) are fundamental building blocks of nanoelectronic circuits. For their emission dynamics as well as for interaction effects such as the 0.7-anomaly the details of the electrostatic potential are important, but…
We measure the conductance of a quantum point contact (QPC) while the biased tip of a scanning probe microscope induces a depleted region in the electron gas underneath. At finite magnetic field we find plateaus in the real-space maps of…
Measurement of a charge qubit via point contacts with complex internal structures is considered. In this context, a fully formalized derivation of the many-body wave function method is presented, together with the corresponding master…
We report charge sensing measurements on a silicon quantum dot (QD) with a nearby silicon single electron transistor (SET) acting as an electrometer. The devices are electrostatically formed in bulk silicon using surface gates. We show that…
Recent experiments performed on weakly pinched quantum point contacts, have shown a resistance that tend to decrease at low source drain voltage. We show that enhanced Coulomb interactions, prompt by the presence of the point contact, may…
The scalability of quantum photonic integrated circuits opens the path towards large-scale quantum computing and communication. To date, this scalability has been limited by the stochastic nature of the quantum light sources. Moreover,…
Quantum detector properties of the quantum point contact (QPC) are analyzed for arbitrary electron transparency and coupling strength to the measured system and are shown to be determined by the electron counting statistics. Conditions of…
We consider charge fluctuations in a quantum dot coupled to an interacting one-dimensional electron liquid. We find the behavior of this system to be similar to the multichannel pseudogap Kondo model. By tuning the coupling between the dot…
We investigate the intensity correlation properties of single photons emitted from an optically excited single semiconductor quantum dot. The second order temporal coherence function of the photons emitted at various wavelengths is measured…
We study a voltage-driven quantum point contact (QPC) strongly coupled to a qubit. We predict pronounced observable features in the QPC current that can be interpreted in terms of half-integer charge transfers. Our analysis is based on the…
We optically probe and electrically control a single artificial molecule containing a well defined number of electrons. Charge and spin dependent inter-dot quantum couplings are probed optically by adding a single electron-hole pair and…
A quantum dot is a sub-micron-scale conducting device containing up to several thousand electrons. Transport through a quantum dot at low temperatures is a quantum-coherent process. This review focuses on dots in which the electron's…
We present a scheme for tuning two quantum point contacts as a quantum-limited charge detector. Based on the scattering matrix approach, we analyze a general condition of quantum-limited detection with a single-channel quantum detector…
The lowest-energy excitations of superconductors do not carry an electric charge, as their wave function is equally electron-like and hole-like. This fundamental property is not easy to study in electrical measurements that rely on the…