Related papers: Superconducting tetrahedral quantum bits
We propose an optimal set of quantum gates for a singlet-triplet qubit in a double quantum dot with two electrons utilizing the $S$-$T_-$ subspace. Qubit rotations are driven by the applied magnetic field and an orthogonal field gradient…
We propose a superconducting qubit circuit that can fully emulate a quantum vector spin-1/2, with an effective dipole moment having three independent components whose operators obey the commutation relations of a vector angular momentum in…
Multi-mode superconducting circuits offer a promising platform for engineering robust systems for quantum computation. Previous studies indicate that single-mode devices cannot be engineered to simultaneously exhibit resilience against…
Superconducting qubits are one of the most promising candidates to implement quantum computers. The superiority of superconducting quantum computers over any classical device in simulating random but well-determined quantum circuits has…
A spin qubit in semiconductor quantum dots holds promise for quantum information processing for scalability and long coherence time. An important semiconductor qubit system is a double quantum dot trapping two electrons or holes, whose spin…
The Fermi-Hubbard model and its rich phase diagram naturally emerges as a description for a wide range of electronic systems. Recent advances in semiconductor-superconductor hybrid quantum dot arrays have allowed to realize degenerate…
We introduce a toy model that allows us to study the physical properties of a spin impurity coupled to the electrons in the superconducting island. We show that when the coupling of the spin is of the order of the superconducting gap two…
An enduring challenge in constructing mechanical oscillator-based hybrid quantum systems is to ensure engineered coupling to an auxiliary degree of freedom while maintaining good mechanical isolation from the environment, that is, low…
The control of discrete quantum states in solids and their use for quantum information processing is complicated by the lack of a detailed understanding of the mechanisms responsible for qubit decoherences. For spin qubits in semiconductor…
Recent experiments by Hayashi et al. [Phys. Rev. Lett. 91, 226804 (2003)] demonstrate coherent oscillations of a charge quantum bit (qubit) in laterally defined quantum dots. We study the intrinsic electron-phonon decoherence and gate…
The concepts of deconfinement and topological order are of great current interest for quantum information science and for our understanding of quantum materials. Here, we introduce a simple model of three antiferromagnetically coupled Kondo…
We show that quantized superconducting circuits are non-integrable at the classical level of description, adorned by nonlinear resonances amidst stochastic sea. The spectral fluctuations of these quasi-integrable systems exhibit…
We calculate the nonequilibrium conductance of a system of two capacitively coupled quantum dots, each one connected to its own pair of conducting leads. The system has been used recently to perform pseudospin spectroscopy by controlling…
(001) Si spin qubits are being intensively studied because they have structures similar to that of CMOS devices currently being produced, and thus have the advantage of utilizing state-of-the-art miniaturization, integration, and…
In many realizations of electron spin qubits the dominant source of decoherence is the fluctuating nuclear spin bath of the host material. The slowness of this bath lends itself to a promising mitigation strategy where the nuclear spin bath…
The time evolution of a qubit, consisting of two single-level quantum dots, is studied in the presence of telegraph noise. The dots are connected by two tunneling paths, with an Aharonov-Bohm flux enclosed between them. Under special…
Two level quantum mechanical systems like spin 1/2 particles lend themselves as a natural qubit implementation. However, encoding a single qubit in several spins reduces the resources necessary for qubit control and can protect from…
In this work, we study a series of tunable flux qubits inductively coupled to a coplanar waveguide resonator fabricated on a sapphire substrate. Each qubit includes an asymmetric superconducting quantum interference device which is…
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…
Measurements indicating that planar networks of superconductive islands connected by Josephson junctions display long range quantum coherence are reported. The networks consist of superconducting islands connected by Josephson junctions and…