Configuration-Interaction Based Simulation of a Quantum Cellular Automaton Cell (2007)
M. Girlanda, M. Governale, M. Macucci, G. Iannaccone
Introduction Logic circuits based on the Quantum Cellular Automaton (QCA) concept have been proposed in the past few years[1] and their implementation with basic cells made up of four quantum dots is...
Configuration-Interaction Based Simulation of a Quantum Cellular Automaton Cell (2007)
M. Girl, M. Governale, M. Macucci, G. Iannaccone
We have investigated the behavior of a quantum cellular automaton cell made up of four quantum dots, in response to the electric field duc to a nearby driver cell. We have implemented a simulation...
G. Iannaccone, C. Ungarelli, M. Macucci, E. Amirante, M. Governale
of a non-invasive charge detector for quantum cellular automata
Landau Cooling in Metal-Semiconductor Nanostructures (2007)
Giazotto, F., Taddei, F., Governale, M., Fazio, R., Beltram, F.
An electron-cooling principle based on Landau quantization is proposed for nanoscale conductor systems. Operation relies on energy-selective electron tunneling into a two-dimensional electron gas in...
Cooling electrons by magnetic-field tuning of Andreev reflection (2006)
Giazotto, F., Taddei, F., Governale, M., Castellana, C., Fazio, R., Beltram, F.
A solid-state cooling principle based on magnetic-field-driven tunable suppression of Andreev reflection in superconductor/two-dimensional electron gas nanostructures is proposed. This cooling...
Superconductor-semiconductor magnetic microswitch (2005)
Castellana, C., Giazotto, F., Governale, M., Taddei, F., Beltram, F.
A hybrid superconductor--two-dimensional electron gas microdevice is presented. Its working principle is based on the suppression of Andreev reflection at the superconductor-semiconductor interface...
Adiabatic pumping in a Superconductor-Normal-Superconductor weak link (2005)
Governale, M., Taddei, F., Hekking, F. W. J., Fazio, Rosario
We present a formalism to study adiabatic pumping through a superconductor - normal - superconductor weak link. At zero temperature, the pumped charge is related to the Berry phase accumulated, in a...
Andreev reflection and cyclotron motion at superconductor -- normal-metal interfaces (2005)
Giazotto, F., Governale, M., Zuelicke, U., Beltram, F.
We investigate Andreev reflection at the interface between a superconductor and a two--dimensional electron system (2DES) in an external magnetic field such that cyclotron motion is important in the...
Two-dimensional hole precession in an all-semiconductor spin field effect transistor (2005)
Pala, M. G., Governale, M., König, J., Zülicke, U., Iannaccone, G.
Desrat, W., Giazotto, F., Pellegrini, V., Governale, M., Beltram, F., Capotondi, F., ...
We report tilted-field transport measurements in the quantum-Hall regime in an InAs/In_0.75Ga_0.25As/In_0.75Al_0.25As quantum well. We observe anti-crossings of spin-split Landau levels, which...
Rashba effect in quantum networks (2005)
Bercioux, D., Governale, M., Cataudella, V., Ramaglia, V.
We present a formalism to study quantum networks made up by single-channel quantum wires in the presence of Rashba spin-orbit coupling and magnetic field. In particular, linear transport through...
Rashba spin splitting in quantum wires (2004)
This article presents an overview of results pertaining to electronic structure, transport properties, and interaction effects in ballistic quantum wires with Rashba spin splitting. Limits of weak...
Rashba-effect-induced localization in quantum networks (2004)
Bercioux, D., Governale, M., Cataudella, V., Ramaglia, V.
We study a quantum network extending in one dimension (chain of square loops connected at one vertex) made up of quantum wires with Rashba spin-orbit coupling. We show that the Rashba effect may give...
Quantum networks in the presence of the Rashba effect and a magnetic field (2004)
Bercioux, D., Governale, M., Cataudella, V., Ramaglia, V.
We use a simple formalism to calculate the conductance of any quantum network consisting of single- channel one-dimensional quantum wires in the presence of Rashba spin-orbit coupling and a coupling...
Pumping spin with electrical fields (2002)
Governale, M., Taddei, F., Fazio, Rosario
Spin currents can be obtained through adiabatic pumping by means of electrical gating only. This is possible by making use of the tunability of the Rashba spin-orbit coupling in semiconductor...
Magnetic Field Effects on the Transport Properties of One-sided Rough Wires (2002)
García-Martín, A., Governale, M., Wölfle, P.
We present a detailed numerical analysis of the effect of a magnetic field on the transport properties of a `small-$N$' one-sided surface disordered wire. When time reversal symmetry is broken due to...
Quantum dots with Rashba spin-orbit coupling (2002)
We present results on the effects of spin-orbit coupling on the electronic structure of few-electron interacting quantum dots. The ground-state properties as a function of the number of electrons in...
Momentum-Resolved Tunneling into Fractional Quantum Hall Edges (2002)
Zuelicke, U., Shimshoni, E., Governale, M.
Tunneling from a two-dimensional contact into quantum-Hall edges is considered theoretically for a case where the barrier is extended, uniform, and parallel to the edge. In contrast to previously...
Spin Accumulation in Quantum Wires with Strong Rashba Spin-Orbit Coupling (2002)
We present analytical and numerical results for the effect of Rashba spin-orbit coupling on band structure, transport, and interaction effects in quantum wires when the spin precession length is...
Filtering spin with tunnel-coupled electron wave guides (2001)
Governale, M., Boese, D., Zuelicke, U., Schroll, C.
We show how momentum-resolved tunneling between parallel electron wave guides can be used to observe and exploit lifting of spin degeneracy due to Rashba spin-orbit coupling. A device is proposed...
Decoherence and dephasing in coupled Josephson qubits (2001)
Governale, M., Grifoni, Milena, Schön, G.
We investigate the decoherence and dephasing of two coupled Josephson qubits. With the interaction between the qubits being generated by current–current correlations, two different situations in...
Probing Spin-Charge Separation in Tunnel-Coupled Parallel Quantum Wires (2001)
Interactions in one-dimensional (1D) electron systems are expected to cause a dynamical separation of electronic spin and charge degrees of freedom. A promising system for experimental observation of...
Operation of Quantum Cellular Automaton cells with more than two electrons (1999)
Girlanda, M., Governale, M., Macucci, M., Iannaccone, G.
We present evidence that operation of QCA (Quantum Cellular Automaton) cells with four dots is possible with an occupancy of 4N+2 electrons per cell (N being an integer). We show that interaction...
Simulation of a non-invasive charge detector for quantum cellular automata (1998)
Iannaccone, G., Ungarelli, C., Macucci, M., Amirante, E., Governale, M.
Information in a Quantum Cellular Automata architecture is encoded in the polarizazion state of a cell, i.e., in the occupation numbers of the quantum dots of which the cell is made up. Non-invasive...
Modeling and manufacturability assessment of bistable quantum-dot cells (1998)
Governale, M., Macucci, M., Iannaccone, G., Ungarelli, C., Martorell, J.
We have investigated the behavior of bistable cells made up of four quantum dots and occupied by two electrons, in the presence of realistic confinement potentials produced by depletion gates on top...
Gauge invariant grid discretization of Schr\"odinger equation (1998)
Using the Wilson formulation of lattice gauge theories, a gauge invariant grid discretization of a one-particle Hamiltonian in the presence of an external electromagnetic field is proposed. This...