Related papers: Spin Qubits in Multi-Electron Quantum Dots
Few-electron systems confined in a quantum dot laterally coupled to a surrounding quantum ring in the presence of an external magnetic field are studied by exact diagonalization. The distribution of electrons between the dot and the ring is…
Effects related with deviations from thermodynamic equilibrium take a special place in the modern physics. Among those, non-equilibrium phenomena in quantum systems attract the highest interest. To date, the experimental technique of spin…
The spin of an electron in a semiconductor quantum dot represents a natural nanoscale solid state qubit. Coupling to nuclear spins leads to decoherence that limits the number of allowed quantum logic operations for this qubit. Traditional…
We present a modulated microwave approach for quantum computing with qubits comprising three spins in a triple quantum dot. This approach includes single- and two-qubit gates that are protected against low-frequency electrical noise, due to…
Quantum computers have the potential to efficiently solve problems in logistics, drug and material design, finance, and cybersecurity. However, millions of qubits will be necessary for correcting inevitable errors in quantum operations. In…
Medium-scale ensembles of coupled qubits offer a platform for near-term quantum technologies including computing, sensing, and the study of mesoscopic quantum systems. Atom-like emitters in solids have emerged as promising quantum memories,…
Control of electron spin decoherence in contact with a mesoscopic bath of many interacting nuclear spins in an InAs quantum dot is studied by solving the coupled quantum dynamics. The nuclear spin bath, because of its bifurcated evolution…
We investigate the spin of a multielectron GaAs quantum dot in a sequence of nine charge occupancies, by exchange coupling the multielectron dot to a neighboring two-electron double quantum dot. For all nine occupancies, we make use of a…
Solid-state systems which mimic two-level atoms are being actively developed. Improving the quantum coherence of these systems, for instance spin qubits or single photon emitters using semiconductor quantum dots, involves dealing with…
We present a variational method to calculate the exchange interactions among donor clusters in a semiconductor. Such clusters are candidates for a so-called control-qubit architecture for quantum information, where the effective exchange…
The quantum levels population behavior of the two coupled flux qubits depending on the external driving field characteristics is studied. The explicit expressions for the multiphoton transition probabilities at an arbitrary control field…
By operating a one-electron quantum dot (fabricated between a multielectron dot and a one-electron reference dot) as a spectroscopic probe, we study the spin properties of a gate-controlled multielectron GaAs quantum dot at the transition…
Electron spin qubit coherence in quantum dots is ultimately limited by random nuclear spin bath fluctuations. Here we aim to eliminate this randomness by making spin bath evolution deterministic. We introduce spin bath control sequences,…
Slow fluctuations of a qubit frequency are one of the major problems faced by quantum computers. To understand their origin it is necessary to go beyond the analysis of their spectra. We show that characteristic features of the fluctuations…
The scalability and power of quantum computing architectures depend critically on high-fidelity operations and robust and flexible qubit connectivity. In this respect, mobile qubits are particularly attractive as they enable dynamic and…
Two-electron charged self-assembled quantum dot molecules exhibit a decoherence-avoiding singlet-triplet qubit subspace and an efficient spin-photon interface. Here, we demonstrate that the cycling transitions originating from auxiliary…
The ability to measure and reduce systematic errors in single-qubit logic gates is crucial when evaluating quantum computing implementations. We describe pulsed electron paramagnetic resonance (EPR) sequences that can be used to measure…
The spin of an electron trapped in a quantum dot is a promising candidate implementation of a qubit for quantum information processing. We study the central spin problem of the effect of the hyperfine interaction between such an electron…
Quantum dot arrays provide a promising platform for quantum information processing. For universal quantum simulation and computation, one central issue is to demonstrate the exhaustive controllability of quantum states. Here, we report the…
Quantum dots are artificial atoms used for a multitude of purposes. Charge defects are commonly present and can significantly perturb the designed energy spectrum and purpose of the dots. Voltage controlled exchange energy in silicon double…