Parabolic Quantum Dot Qubit Research Articles

Influences of the Temperature on the Parabolic Quantum Dot Qubit in the Magnetic Field

Using the variational method of the Pekar type, we study the influences of the temperature on the parabolic quantum dot qubit in the magnetic field under the condition of electric–LO-phonon strong coupling. Then we derive the numerical results and formulate the derivative relationships of the oscillation period of the electron in the superposition state of the ground state and the first-excited state with the magnetic field, the electron–LO-phonon coupling constant and the confinement length at different temperatures, respectively.

Effects of Temperature and Magnetic Field on the Coherence Time of a RbCl Parabolic Quantum Dot Qubit

Employing the Pekar variational method, quantum statistics theory and the Fermi golden rule, the temperature and magnetic field effects on the qubit in rubidium chloride (RbCl) parabolic quantum dots (PQDs) are investigated. We then obtain the eigenenergies and corresponding eigenfunctions of ground and first-excited states coupled strongly to an electron to bulk longitudinal optical phonons in a RbCl PQD with applied magnetic field. A two-level system of PQDs may be regarded as a single qubit. The spontaneous emission of phonons causes the qubit decoherence. The numerical results indicate that the coherence time decreases with elevating temperature. The coherence increases the effective confinement length, whereas there is a decrease of the magnetic field’s cyclotron frequency.

The effect of electric field on the coherence time of a 2D RbCl parabolic quantum dot qubit

The effects of the electric field on the coherence time of a 2D RbCl parabolic quantum dot (PQD) qubit are studied by using the variational method of Pekar type (VMPT) and the Fermi Golden Rule. We calculate the excitation energy of an electron strongly coupled to bulk longitudinal optical (LO) phonons in the 2D RbCl PQD under an applied electric field. The phonon spontaneous emission causes the decoherence of the qubit. The investigated results indicate that the coherence time increases with increasing strength of the electric field and the effective confinement length, whereas it decreases with increasing polaron radius. Our research results would be useful for the design and implementation of the solid-state quantum computation.

Effects of Temperature and Electric Field on the Coherence Time of a RbCl Parabolic Quantum Dot Qubit

We study the effects of the temperature and electric field on the coherence time of a RbCl parabolic quantum dot (PQD) qubit by using the variational method of Pekar type, the Fermi Golden Rule and the quantum statistics theory (VMPTFGRQST). The ground and the first excited states’ (GFES) eigenenergies and the eigenfunctions of an electron in the RbCl PQD with an applied electric field are derived. A single qubit can be realized in this two-level quantum system. It turns out that the coherence time is a decreasing function of the temperature and the electric field, whereas it is an increasing one of the effective confinement length (ECL). By changing the electric field, the temperature and the ECL one can adjust the coherence time. Our research results may be useful for the design and implementation of solid-state quantum computation.

Effects of temperature and hydrogen-like impurity on the coherence time of RbCl parabolic quantum dot qubit

By using a variational method of Pekar type, the Fermi Golden Rule and the quantum statistics theory (VMPTFGRQST), we investigate the effects of the hydrogen-like impurity and temperature on the coherence time of a parabolic quantum dot (PQD) qubit with a hydrogen-like impurity at the center. We then derive the ground and the first excited states' (GFES) eigenenergies and the eigenfunctions in a PQD. A single qubit can be realized in this two-level quantum system. The phonon spontaneous emission causes the decoherence of the qubit. The numerical results show that the coherence time is a decreasing function of the temperature, the strength of the Coulombic impurity potential (CIP) and the polaron radius (PR).

Effect of temperature on the coherence time of a parabolic quantum dot qubit

The effects of the temperature on the coherence time of a parabolic quantum dot (PQD) qubit are investigated by using the variational method of Pekar type. We obtain the ground and the first excited states’ eigenenergies and the corresponding eigenfunctions of an electron strongly coupled to bulk longitudinal optical phonons in the PQD. This two-level PQD system may be employed as a single qubit. The phonon spontaneous emission causes the decoherence of the qubit. We find that the coherence time will decrease with increasing temperature. It is an increasing function of the effective confinement length, whereas it is decreasing one of the polaron radius. We find that by changing the temperature, the effective confinement length and the polaron radius one can adjust the coherence time. Our research results would be useful for the design and implementation of the solid-state quantum computation.

Effects of Magnetic Field on the Coherence Time of a Parabolic Quantum Dot Qubit

We obtain the eigenenergies and eigenfunctions (EE) of the ground and first excited states of an electron strongly coupled to LO-phonon in a parabolic quantum dot. The effect of an applied magnetic field is considered by using variational method of Pekar type. This system may be regarded as a two-level qubit. Spontaneous phonon emission arouses the qubit’s decoherence. Relations between the coherence time (CT) and the magnetic field, the effective confinement length (ECL) and the polaron radius (PR) are numerically calculated. It is found that the CT is an increasing function of the ECL, whereas it is a decreasing one of the cyclotron frequency and PR. We can extend the CT by changing these parameters in the correlated quantum functional devices.

The Temperature Effects on the Parabolic Quantum Dot Qubit in the Electric Field

The temperature effects on the parabolic quantum dot qubit in the electric field have been studied under the condition of electric-LO-phonon strong coupling using the variational method of Pekar type. The numerical results lead us to formulate the derivative relationships of the oscillation period of the electron in the superposition state of the ground state and the first-excited state with the electric field, the electron-LO-phonon coupling constant and the confinement length at different temperatures, respectively.

The Effect of Magnetic on the Properties of a Parabolic Quantum Dot Qubit

On the condition of electric-LO phonon strong coupling in a parabolic quantum dot, we obtained the eigen energies and the eigenfunctions of the ground state and the first excited state by using the variational method of Pekar type. This system in a quantum dot may be employed as a two-level quantum system qubit. When the electron is in the superposition state of the ground state and the first excited state, we obtained the space-time evolution of the electron density. The relations on the cyclotron frequency with the electron probability density and the period of oscillation are derived in a parabolic quantum dot.

The decoherence of the two- and three-dimensional parabolic quantum dot qubit

On the condition of electric-LO phonon strong coupling in a two- and three-dimensional parabolic quantum dot (QD), we obtain the eigenenergies of the ground state and the first-excited state, the eigenfunctions of the ground state and the first-excited state by using variational method of Pekar type. This system in QD may be employed as a quantum system-qubit. The phonon spontaneous emission causes the decoherence of the qubit. The relations between the decoherence time with the coupling strength, the confinement length, the coefficient dispersion are discussed.

The influence of electric field on a parabolic quantum dot qubit

This paper calculates the time evolution of the quantum mechanical state of an electron by using variational method of Pekar type on the condition of electric–LO-phonon strong coupling in a parabolic quantum dot. It obtains the eigenenergies of the ground state and the first-excited state, the eigenfunctions of the ground state and the first-excited state This system in a quantum dot may be employed as a two-level quantum system qubit. The superposition state electron density oscillates in the quantum dot with a period when the electron is in the superposition state of the ground and the first-excited state. It studies the influence of the electric field on the eigenenergies of the ground state, the first-excited state and the period of oscillation at the different electron–LO-phonon coupling constant and the different confinement length.

The effect of Coulomb potential to the decoherence of the parabolic quantum dot qubit

On the condition of electric-LO phonon strong coupling in parabolic quantum dot, we obtained the eigenenergy of the ground state and the first excited state, the eigenfuctions of the ground state and the first excited state by using variational method of Pekar type. This system of quantum dot may be employed as a two-level quantum system-qubit. The phonon spontaneous emission causes the decoherence of the qubit. We discussed the relatoion between the decoherence time and the Coulomb binding parameter，the couping strength, the confinement length, and the conefficient dispersion.