Related papers: Dangling-bond charge qubit on a silicon surface

We devise a scheme to characterize tunneling of an excess electron shared by a pair of tunnel-coupled dangling bonds on a silicon surface -- effectively a two-level system. Theoretical estimates show that the tunneling should be highly…

Silicon-based dangling-bond charge qubit is one of the auspicious models for universal fault-tolerant solid-state quantum computing. In universal quantum computing, it is crucial to evaluate and characterize the computational Hilbert space…

Spin qubits based on Si and Si$_{1-x}$Ge$_{x}$ quantum dot architectures exhibit among the best coherence times of competing quantum computing technologies, yet they still suffer from charge noise that limit their qubit gate fidelities.…

Silicon-based quantum-computer architectures have attracted attention because of their promise for scalability and their potential for synergetically utilizing the available resources associated with the existing Si technology…

Here we report the direct observation of single electron charging of a single atomic Dangling Bond (DB) on the H-Si(100) 2x1 surface. The tip of a scanning tunneling microscope is placed adjacent to the DB to serve as a single electron…

We study entanglement of charge qubits in a vertical tunnel-coupled double quantum dot containing two interacting electrons. Exact diagonalization is used to compute the negativity characterizing entanglement. We find that entanglement can…

We review our recent efforts in building atom-scale quantum-dot cellular automata circuits on a silicon surface. Our building block consists of silicon dangling bond on a H-Si(001) surface, which has been shown to act as a quantum dot.…

In recent years, quantum computing has promised a revolution in computing performance, based on massive parallelism enabled by many entangled qubits. Josephson junction integrated circuits have emerged as the key technology to implement…

We theoretically examine the capacitive coupling between two quantum dot hybrid qubits, each consisting of three electrons in a double quantum dot, as a function of the energy detuning of the double dot potentials. We show that a shaped…

It has long been anticipated that the ultimate in miniature circuitry will be crafted of single atoms. Despite many advances made in scanned probe microscopy studies of molecules and atoms on surfaces, challenges with patterning and limited…

Paramagnetic point defects in silicon provide qubits that could open up pathways towards silicon-technology based, low-cost, room-temperature (RT) quantum sensing. The silicon dangling bond (db) is a natural candidate, given its…

A system, comprised of a qubit pair coupled to a common cavity, is studied with the aim of establishing qubit entanglement. This study is the sequel of the paper Phys. Rev. A 111, 043705 (2025), where similar model was investigated for an…

Surface defects created and probed with scanning tunneling microscopes are a promising platform for atomic-scale electronics and quantum information technology applications. Using first-principles calculations we demonstrate how to engineer…

Designing coherent processes is essential for developing quantum information technologies. We study coherent dynamics of two spatially separated electrons in a coupled semiconductor double quantum dot (DQD), in which various two-qubit…

We demonstrate conditional entanglement swapping, i.e. teleportation of entanglement, between time-bin qubits at the telecommunication wavelength of 1536.4 nm with high fidelity of 87\%. Our system is deployable, utilizing modular,…

Entanglement swapping, the process to entangle two particles without coupling them in any way, is one of the most striking manifestations of the quantum-mechanical nonlocal characteristic. Besides fundamental interest, this process has…

We consider a collection of two level systems, such as qubits, embedded into a microwave cavity as a promising candidate for the realization of high power quantum batteries. In this perspective, the possibility to design devices where the…

Collective quantum batteries (QBs) demonstrate remarkable acceleration in charging dynamics compared to their individual counterparts, underscoring the pivotal contribution of quantum correlations to advanced energy storage paradigms. A…

It is discovered that the zero-dimensional character of the silicon atom dangling bond (DB) state allows controlled formation and occupation of a new form of quantum dot assemblies. Whereas on highly doped n-type substrates isolated DBs are…

The dynamics of charge qubit in a double quantum dot coupled to phonons is investigated theoretically in terms of a perturbation treatment based on a unitary transformation. The dynamical tunneling current is obtained explicitly. The result…