Related papers: Exchange-controlled single-electron-spin rotations…
We perform time-dependent simulations of spin exchange for an electron pair in laterally coupled quantum dots. The calculation is based on configuration interaction scheme accounting for spin-orbit (SO) coupling and electron-electron…
Tailoring spin coupling to electric fields is central to spintronics and spin-based quantum information processing. We present an optimal micromagnet design that produces appropriate stray magnetic fields to mediate fast electrical spin…
Electron spins in quantum dots under coherent control exhibit a number of novel feedback processes. Here, we present experimental and theoretical evidence of a feedback process between nuclear spins and a single electron spin in a single…
We present an approach for entangling electron spin qubits localized on spatially separated impurity atoms or quantum dots via a multi-electron, two-level quantum dot. The effective exchange interaction mediated by the dot can be understood…
In a GaAs single quantum dot, the relaxation time T_{1} between spin triplet and singlet states has been measured for the last few even number of electrons. The singlet-triplet energy separation E_{ST} is tuned as a control parameter for…
A method is proposed for the optical rotation of the spin of an electron in a quantum dot using excited trion states to implement operations up to two orders of magnitude faster than those of most existing proposals. Key ingredients are the…
We are pursuing a capability to perform time resolved manipulations of single spins in quantum dot circuits involving more than two quantum dots. In this paper, we demonstrate full counting statistics as well as averaging techniques we use…
The spin states of electrons and holes confined in InAs quantum dot molecules have recently come to fore as a promising system for the storage or manipulation of quantum information. We describe here a feasible scheme for complete quantum…
Single electron spins in quantum dots are attractive for quantum communication because of their expected long coherence times. We propose a method to create entanglement between two remote spins based on the coincident detection of two…
We have investigated the realizability of the controlled-NOT (CNOT) gate and characterized the gate operation by quantum process tomography for a chain of qubits, realized by electrons confined in self-assembled quantum dots embedded in the…
We present measurements on nuclear spin relaxation probed by a single quantum dot in a high-mobility electron gas. Current passing through the dot leads to a spin transfer from the electronic to the nuclear spin system. Applying electron…
For the realisation of scalable solid-state quantum-bit systems, spins in semiconductor quantum dots are promising candidates. A key requirement for quantum logic operations is a sufficiently long coherence time of the spin system.…
A single hole spin in a semiconductor quantum dot has emerged as a quantum bit that is potentially superior to an electron spin. A key feature of holes is that they have a greatly reduced hyperfine interaction with nuclear spins, which is…
The Heisenberg exchange interaction between neighboring quantum dots allows precise voltage control over spin dynamics, due to the ability to precisely control the overlap of orbital wavefunctions by gate electrodes. This allows the study…
Qubits encoded in a decoherence-free subsystem and realized in exchange-coupled silicon quantum dots are promising candidates for fault-tolerant quantum computing. Benefits of this approach include excellent coherence, low control…
We show how to eliminate the first-order effects of the spin-orbit interaction in the performance of a two-qubit quantum gate. Our procedure involves tailoring the time dependence of the coupling between neighboring spins. We derive an…
Quantum dots realized in InAs are versatile systems to study the effect of spin-orbit interaction on the spin coherence, as well as the possibility to manipulate single spins using an electric field. We present transport measurements on…
We present a novel scheme for performing a conditional phase gate between two spin qubits in adjacent semiconductor quantum dots through delocalized single exciton states, formed through the inter-dot Foerster interaction. We consider two…
The three-spin-$1/2$ decoherence-free subsystem defines a logical qubit protected from collective noise and supports exchange-only universal gates. Such logical qubits are well-suited for implementation with electrically-defined quantum…
We show how to construct a universal set of quantum logic gates using control over exchange interactions and single- and two-spin measurements only. Single-spin unitary operations are teleported instead of being executed directly, thus…