相关论文: Dynamic Nuclear Polarization with Single Electron …

We report on the dynamic nuclear polarization of a single charge-tunable self-assembled InAs/GaAs quantum dot in a longitudinal magnetic field of $\sim$0.2T. The hyperfine interaction between the optically oriented electron and nuclei spins…

We theoretically investigate the controlled dynamic polarization of lattice nuclear spins in GaAs double quantum dots containing two electrons. Three regimes of long-term dynamics are identified, including the build up of a large difference…

We propose a new mechanism for polarizing nuclear spins in quantum dots, based on periodic modulation of the hyperfine coupling by electric driving at the electron spin resonance frequency. Dynamical nuclear polarization results from…

The electron-nuclei (hyperfine) interaction is central to spin qubits in solid state systems. It can be a severe decoherence source but also allows dynamic access to the nuclear spin states. We study a double quantum dot exposed to an…

We theoretically study the dynamic polarization of lattice nuclear spins in GaAs double quantum dots containing two electrons. In our prior work [Phys. Rev. Lett. 104, 226807 (2010)] we identified three regimes of long-term dynamics,…

We theoretically investigate dynamic nuclear spin polarization in a self-assembled quantum dot pumped optically by two laser beams. With the assumption that a noncollinear interaction between the hole spin and nuclear spins leads to nuclear…

We demonstrate dynamical nuclear spin polarization in the absence of an external magnetic field, by resonant circularly polarized optical excitation of a single electron or hole charged quantum dot. Optical pumping of the electron spin…

We proposed and demonstrated that the nuclear spins of the host lattice in GaAs double quantum dots can be strongly polarized in either of two opposite directions, parallel or antiparallel to an external magnetic field. The direction is…

We demonstrate a new method for electrical manipulation of nuclear spins utilizing dynamic nuclear polarization induced by quantum Hall effect breakdown. Nuclear spins are polarized and detected through the hyperfine interaction between a…

We studied the zero-field dynamic nuclear spin polarization in a single In$_{0.75}$Al$_{0.25}$As/Al$_{0.3}$Ga$_{0.7}$As quantum dot. Even without any external magnetic field, the positive trion excited by the circularly-polarized light…

Highly polarized nuclear spins within a semiconductor quantum dot (QD) induce effective magnetic (Overhauser) fields of up to several Tesla acting on the electron spin or up to a few hundred mT for the hole spin. Recently this has been…

Magnetic noise of atomic nuclear spins is a major problem for solid state spin qubits. Highly-polarized nuclei would not only overcome this obstacle, but also make nuclear spins a useful quantum information resource. However, achieving…

Dynamic nuclear polarization transfers spin polarization from electrons to nuclei. We have achieved this by a new method, simultaneously exciting transitions of electronic and nuclear spins. The efficiency of this technique improves with…

In III-V semiconductor nano-structures the electron and nuclear spin dynamics are strongly coupled. Both spin systems can be controlled optically. The nuclear spin dynamics is widely studied, but little is known about the initialization…

A dynamical nuclear polarization scheme is studied in gated double dots. We demonstrate that a small polarization ($\sim 0.5%$) is sufficient to enhance the singlet decay time by two orders of magnitude. This enhancement is attributed to an…

The representation of information within the spins of electrons and nuclei has been powerful in the ongoing development of quantum computers. Although nuclear spins are advantageous as quantum bits (qubits) due to their long coherence…

We investigate the dynamic nuclear polarization from the hyperfine interaction between nonequilibrium electronic spins and nuclear spins coupled to them in semiconductor nanostructures. We derive the time and position dependence of the…

Spontaneous nuclear polarization is predicted in double quantum dots in the spin-blocked electron transport regime. The polarization results from an instability of the zero-polarization state when singlet and triplet electron energy levels…

Hyperfine coupling of electron spins to nuclear spins is studied for a GaAs-based double quantum dot in the spin blockade regime where the electron conduction is mostly blocked by Pauli effect unless the electron spin state in the double…

We investigate the dynamic polarization of nuclear spins in a nominally undoped GaAs/Al$_{0.35}$Ga$_{0.65}$As quantum well using two complementary experimental approaches: time-resolved Kerr rotation and optical orientation measurements of…