Related papers: Magnetization of Nuclear-Spin-Polarization-Induced…
We performed a nuclear magnetometry study on quantum Hall ferromagnet with a bilayer total filling factor of $\nu_{\rm{tot}} = 2$. We found not only a rapid nuclear relaxation but also a sudden change in the nuclear spin polarization…
We show that nuclear spin subsystems can be completely controlled via microwave irradiation of resolved anisotropic hyperfine interactions with a nearby electron spin. Such indirect addressing of the nuclear spins via coupling to an…
We review our theoretical work on the dynamics of a localized electron spin interacting with an environment of nuclear spins. Our perturbative calculation is valid for arbitrary polarization p of the nuclear spin system and arbitrary…
Electrically detected electron spin resonance (ESR) is used to study the hyperfine interaction of the two-dimensional electrons and the nuclei of the host lattice in a GaAs/AlGaAs heterostructure. Under the microwave and radio- frequency…
We have studied theoretically the electron spin relaxation in semiconductor quantum dots via interaction with nuclear spins. The relaxation is shown to be determined by three processes: (i) -- the precession of the electron spin in the…
We show that a quantum wire device with spin splitting can work as an active spin polarizer. Hot electrons in one `spin' subband (e.g. `spin-up') may pass such a device with weak electron pair scattering, while electrons in the opposite…
A classical circularly polarized electromagnetic wave carries angular momentum, and represents the classical limit of a photon, which carries quantized spin. It is shown that a very similar picture of a circularly polarized coherent wave…
We have studied the spin structure of circular four-electron quantum rings using tunable confinement potentials. The calculations were done using the exact diagonalization method. Our results indicate that ringlike systems can have…
A coherent superposition of many nuclear spin states can be prepared and manipulated via the hyperfine interaction with the electronic spins by varying the Landau level filling factor through the gate voltage in appropriately designed…
A key to achieving ultra-long electron spin memory in quantum dots (QDs) at 0~$T$ is the polarization of the nuclei, such that the electron spin is stabilized along the nuclear magnetic field. We demonstrate that spin-polarized electrons in…
Nuclear-spin qubits have long coherence time and are desirably applied into quantum information processing. However, the existing methods either fail to address single nucleus (such as nuclear magnetic resonance), or severely affect nuclear…
Semiconductor quantum dots provide a spin-coupled system of an electron and nuclei via enhanced hyperfine interaction. We showed that the nuclear spin polarization in single quantum dots can have three stable branches under a longitudinal…
The backscattering process of injected electrons on exchange-splitted levels of quantum well (QW) in ferromagnetic metal / insulator / semiconductor heterostructure is studied. It is found that, if one of the exchange-splitted levels lies…
We observe nuclear magnetic resonance (NMR) in the fractional quantum Hall regime at Landau level filling factor $\nu=2/3$ from simultaneous measurement of longitudinal resistance and photoluminescence (PL). The dynamic nuclear spin…
The nuclear spins in nanostructured semiconductors play a central role in quantum applications. The nuclear spins represent a useful resource for generating local magnetic fields but nuclear spin noise represents a major source of dephasing…
Electrical control of spins at the nanoscale offers significant architectural advantages in spintronics, because electric fields can be confined over shorter length scales than magnetic fields. Thus, recent demonstrations of electric-field…
Optical pump-probe techniques are used to generate and measure electron spin polarization in a gallium arsenide epilayer in which the electron spin coherence time exceeds the mode-locked laser repetition period. Resonant spin amplification…
We study a mechanism by which nuclear hyperpolarization due to the polarization transfer from a microwave-pulse-controlled electron spin is suppressed. From analytical and numerical calculations of the unitary dynamics of multiple nuclear…
By means of ab initio calculations and spin-polarized scanning tunneling microscopy experiments we show how to manipulate the local spin-polarization of a ferromagnetic surface by creating a complex energy dependent magnetic structure. We…
The total energy of a quasi-one-dimensional electron system is calculated using density functional theory. It is shown that spontaneous ferromagnetic state in quantum wire occurs at low one-dimensional electron density. The critical…