Related Experiment Video
Updated: Jun 19, 2026
06:42
Generation and Coherent Control of Pulsed Quantum Frequency Combs
Published on: June 8, 2018
Correlated coherent oscillations in coupled semiconductor charge qubits.
Gou Shinkai1, Toshiaki Hayashi, Takeshi Ota
1NTT Basic Research Laboratories, NTT Corporation, 3-1 Morinosato-Wakamiya, Atsugi, 243-0198, Japan.
Physical Review Letters
|October 2, 2009
Summary
We observed that two electrons in coupled quantum dots exhibit coherent oscillations, enabling two-qubit operations. This research highlights the potential for quantum entanglement in electronic devices.
Area of Science:
- Quantum physics
- Condensed matter physics
- Quantum computing
Background:
- Semiconductor double quantum dots (DQDs) are promising platforms for quantum information processing.
- Understanding coherent electron dynamics is crucial for developing quantum technologies.
Purpose of the Study:
- To investigate the coherent dynamics of two spatially separated electrons in a coupled semiconductor double quantum dot (DQD).
- To interpret observed coherent oscillations as fundamental two-qubit quantum operations.
- To explore the potential for quantum entanglement in scalable electronic devices.
Main Methods:
- Utilizing a coupled semiconductor double quantum dot (DQD) system.
- Observing and analyzing coherent oscillations of electron states.
- Interpreting the dynamics in terms of two-qubit gate operations.
Main Results:
- Coherent oscillations in one DQD are significantly influenced by the states of the other DQD.
- Electrons exhibit correlated tunneling behavior.
- Observed oscillations demonstrate feasibility of various two-qubit operations.
Conclusions:
- The coherent dynamics in coupled DQDs can be harnessed for quantum operations.
- The findings encourage further research into quantum entanglement within electronic devices.
- This work paves the way for solid-state quantum information processing.
Related Concept Videos
01:30Oscillations In An LC Circuit
An idealized LC circuit of zero resistance can oscillate without any source of emf by shifting the energy stored in the circuit between the electric and magnetic fields. In such an LC circuit, if the capacitor contains a charge q before the switch is closed, then all the energy of the circuit is initially stored in the electric field of the capacitor. This energy is given by
01:12Fermi Level Dynamics
The vacuum level denotes the energy threshold required for an electron to escape from a material surface. It is usually positioned above the conduction band of a semiconductor and acts as a benchmark for comparing electron energies within various materials.
Electron affinity in semiconductors refers to the energy gap between the minimum of its conduction band and the vacuum level and it is a critical parameter in determining how easily a semiconductor can accept additional electrons.
The work...
Electron affinity in semiconductors refers to the energy gap between the minimum of its conduction band and the vacuum level and it is a critical parameter in determining how easily a semiconductor can accept additional electrons.
The work...
02:45The Quantum-Mechanical Model of an Atom
Shortly after de Broglie published his ideas that the electron in a hydrogen atom could be better thought of as being a circular standing wave instead of a particle moving in quantized circular orbits, Erwin Schrödinger extended de Broglie’s work by deriving what is now known as the Schrödinger equation. When Schrödinger applied his equation to hydrogen-like atoms, he was able to reproduce Bohr’s expression for the energy and, thus, the Rydberg formula governing hydrogen spectra. Schrödinger...
01:11Atomic Nuclei: Larmor Precession Frequency
The earth's gravitational field produces a 'twisting force' perpendicular to the angular momentum of a spinning mass (such as a spinning top) that causes the mass to 'wobble' around the gravitational field axis in a phenomenon called precession. Similarly, the magnetic moment (μ) of a spinning nucleus precesses due to an external magnetic field directed along the z-axis. The precession of the magnetic moment vector about the magnetic field is called Larmor precession, and the angular frequency...
01:21Energy Associated With a Charge Distribution
The work done to bring a charge through a distance r is given by the potential difference between the initial and the final position. To assemble a collection of point charges, the total work done can be expressed in terms of the product of each pair of charges divided by their separation distance, defined with respect to a suitable origin. Solving this expression gives the energy stored in a point charge distribution.
01:20Spin–Spin Coupling: Two-Bond Coupling (Geminal Coupling)
Two NMR-active nuclei bonded to a central atom can be involved in geminal or two-bond coupling. Geminal coupling is commonly seen between diastereotopic protons in chiral molecules and unsymmetrical alkenes, among others.
The central atom need not be NMR-active because its electrons are affected by the electron polarization of the spin-active atoms. However, spin information is transmitted less effectively than in one-bond coupling, and 2J values are usually weaker than 1J values. The energy of...
The central atom need not be NMR-active because its electrons are affected by the electron polarization of the spin-active atoms. However, spin information is transmitted less effectively than in one-bond coupling, and 2J values are usually weaker than 1J values. The energy of...