Gerd Schoen

Conductance of a hydrogen molecule (2002)

Heurich, J., Pauly, F., Cuevas, J. C., Wenzel, W., Schoen, Gerd

Recently Smit et al. [Nature 419, 906 (2002)] have reported that a single hydrogen molecule can form a bridge between Pt electrodes, which has a conductance close to one quantum unit, carried by a...

Quantum state engineering with Josephson-junction devices (2000)

Makhlin, Yuriy, Schoen, Gerd, Shnirman, Alexander

We review recent theoretical and experimental progress in quantum state engineering with Josephson junction devices. The concepts of quantum computing have stimulated an increased activity in the...

Non-equilibrium supercurrent through mesoscopic ferromagnetic weak links (2000)

Heikkila, Tero T., Wilhelm, Frank K., Schoen, Gerd

We consider a mesoscopic normal metal, where the spin degeneracy is lifted by a ferromagnetic exchange field or Zeeman splitting, coupled to two superconducting reservoirs. As a function of the...

Statistics and noise in a quantum measurement process (2000)

Makhlin, Yuriy, Schoen, Gerd, Shnirman, Alexander

The quantum measurement process by a single-electron transistor or a quantum point contact coupled to a quantum bit is studied. We find a unified description of the statistics of the monitored...

Nano-electronic Realizations of Quantum Bits (1999)

Makhlin, Yuriy, Schoen, Gerd, Shnirman, Alexander

Quantum computers could perform certain tasks which no classical computer can perform in acceptable times. Josephson junction circuits can serve as building blocks of quantum computers. We discuss...

Superconducting single-charge transistor in a tunable dissipative environment (1999)

Wilhelm, Frank K., Schoen, Gerd, Zimanyi, Gergely T.

We study a superconducting single-charge transistor, where the coherence of Cooper pair tunneling is destroyed by the coupling to a tunable dissipative environment. Sequential tunneling and...

Andreev Reflection in Strong Magnetic Fields (1999)

Hoppe, H., Zuelicke, U., Schoen, Gerd

We have studied the interplay of Andreev reflection and cyclotron motion of quasiparticles at a superconductor-normal-metal interface with a strong magnetic field applied parallel to the interface....

Josephson-Junction Qubits and the Readout Process by Single-Electron Transistors (1998)

Makhlin, Yuriy, Schoen, Gerd, Shnirman, Alexander

Several physical realizations of quantum bits have been proposed. Of those, nano-electronic devices appear most suitable for large-scale integration and potential applications. We suggest to use...

Josephson-Junction Qubits with Controlled Couplings (1998)

Makhlin, Yuriy, Schoen, Gerd, Shnirman, Alexander

Low-capacitance Josephson junctions, where Cooper pairs tunnel coherently while Coulomb blockade effects allow the control of the total charge, provide physical realizations of quantum bits (qubits),...

Quantum Measurements Performed with a Single-Electron Transistor (1998)

Shnirman, Alexander, Schoen, Gerd

Low-capacitance Josephson junction systems as well as coupled quantum dots, in a parameter range where single charges can be controlled, provide physical realizations of quantum bits, discussed in...

A New Quantum Phase Transition in the Coupled Quantum Dots System (1997)

Andrei, Natan, Zimanyi, Gergely T., Schoen, Gerd

We study two quantum dots in the limit of strong dot-lead coupling and weak dot-dot tunneling. The model maps on Ising-coupled Kondo impurities. We argue that a new quantum critical fixed point...

Quantum Manipulations of Small Josephson Junctions (1997)

Shnirman, Alexander, Schoen, Gerd, Hermon, Ziv

Low-capacitance Josephson junction arrays in the parameter range where single charges can be controlled are suggested as possible physical realizations of the elements which have been considered in...

Duality in Josephson Junction Arrays (1997)

Blanter, Ya. M., Fazio, Rosario, Schoen, Gerd

Various properties of mesoscopic two-dimensional Josephson junction arrays are reviewed. Particular attention is paid to structure of the topological excitations, charges and vortices, which are...