Related papers: Quantum control of a model qubit based on a multi-…
We study generation and dynamics of an exchange spin qubit encoded in three coherently coupled quantum dots with three electrons. For two geometries of the system a linear and a triangular one, the creation and coherent control of the qubit…
The quantum state of a flux qubit was successfully pulse-controlled by using a resonant microwave. We observed Ramsey fringes by applying a pair of phase-shifted pi/2 microwave pulses without introducing detuning. With this method, the…
The many-body state of carriers confined in a quantum dot is controlled by the balance between their kinetic energy and their Coulomb correlation. In coupled quantum dots, both can be tuned by varying the inter-dot tunneling and…
A quantum system subject to external fields is said to be controllable if these fields can be adjusted to guide the state vector to a desired destination in the state space of the system. Fundamental results on controllability are reviewed…
This paper presents a sampled-data approach for the robust control of a single qubit (quantum bit). The required robustness is defined using a sliding mode domain and the control law is designed offline and then utilized online with a…
The Coulomb interactions between electrons play important roles in coupling multiple qubits in various quantum systems. Here we demonstrate controlled quantum operations of three electron charge qubits based on three capacitively coupled…
he multiqubit entangled states are coherently controlled in the quantum spin systems composed of $N+1$ interacting antiferromagnetic molecular rings. The tunable intermolecular couplings arise from the local exchange interactions between…
Spin qubits are contenders for scalable quantum computation because of their long coherence times demonstrated in a variety of materials, but individual control by frequency-selective addressing using pulsed spin resonance creates severe…
We use a bulk acoustic wave resonator to demonstrate coherent control of the excited orbital states in a diamond nitrogen-vacancy (NV) center at cryogenic temperature. Coherent quantum control is an essential tool for understanding and…
Quantum state manipulation with gates based on geometric phases acquired during cyclic operations promises inherent fault-tolerance and resilience to local fluctuations in the control parameters. Here we create a general non-Abelian and…
In the design of quantum computing devices of the future the basic element is the qubit. It is a two-level quantum system which may describe population transfer from one steady-state to another controlled by a coherent laser field. A…
The coherent time evolution of electrons in double quantum dots induced by fast bias-voltage switches is studied theoretically. As it was shown experimentally, such driven double quantum dots are potential devices for controlled…
We apply an invariant-based inverse engineering method to control by time-dependent electric fields electron spin dynamics in a quantum dot with spin-orbit coupling in a weak magnetic field. The designed electric fields provide a shortcut…
In a digital quantum simulator, basic two-qubit interactions are manipulated by means of fast local control operations to establish a desired target Hamiltonian. Here we consider a quantum simulator based on logical systems, i.e. where…
A two-qutrit extension of the quantum Rabi model is studied. Despite its increased complexity, the model results to be integrable under specific, physically relevant conditions. This feature allows for the emergence of analytically…
By moving the pivot of a pendulum rapidly up and down one can create a stable position with the pendulum's bob above the pivot rather than below it. This surprising and counterintuitive phenomenon is a widespread feature of driven systems…
We show that resonant driving between the spin up and spin down states of an electron spin-qubit in a quantum dot reduces the occupancy of the dot through leakage to an appropriately tuned lead. A nearby charge sensor measuring the…
We investigate coherent time-evolution of charge states (pseudo-spin qubit) in a semiconductor double quantum dot. This fully-tunable qubit is manipulated with a high-speed voltage pulse that controls the energy and decoherence of the…
We have studied interactions between two capacitively coupled GaAs/AlGaAs few-electron double quantum dots. Each double quantum dot defines a tunable two-level system, or qubit, in which a single excess electron occupies either the ground…
Quantum systems can be controlled by other quantum systems in a reversible way, without any information leaking to the outside of the system-controller compound. Such coherent quantum control is deterministic, is less noisy than…