Related papers: Time-optimal polarization transfer from an electro…
The usual theoretical model for synchrotron radiation in circular accelerators (synchrotrons and storage rings) is to treat a single electron moving in a horizontal circle in a uniform vertical magnetic field, but the true situation in real…
We experimentally demonstrate a method for obtaining nuclear spin hyperpolarization, that is, polarization significantly in excess of that expected for a thermal equilibrium. By exploiting a modified Overhauser process, we obtain more than…
Dynamic nuclear polarization (DNP) is an attractive method for initializing nuclear spins that are strongly coupled to optically active electron spins because it functions at room temperature and does not require strong magnetic fields. In…
Here, we demonstrate the radiative polarization of high-energy electron beams in collisions with ultrashort pulsed bi-chromatic laser fields. Employing a Boltzmann kinetic approach for the electron distribution allows us to simulate the…
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…
For the model Hamiltonian describing the electron-nuclear dynamics of a quantum dot, we obtained an exact expression for the limiting nuclear polarization as a function of the number of groups of equivalent nuclei. It is shown that the…
This thesis examines some of the more fundamental requirements of a successful quantum computation, namely the ability to transmit quantum information with maximum efficiency, and the creation of entanglement. I focus specifically on…
Nuclear spins in quantum dots are promising candidates for fast and scalable quantum memory. By utilizing the hyperfine interaction between the central electron and its surrounding nuclei, quantum information can be transferred to the…
A method of ultrafast switching of ferroelectric polarization is suggested. The method is based on the interaction of a ferroelectric sample with the feedback field of a resonator in which the sample is inserted. The polarization reversal…
We show that electrons recolliding with the ionic core upon tunnel ionization of noble gas atoms driven by a strong circularly polarized laser field in combination with a counter-rotating second harmonic are spin polarized and that their…
Spin transfer in high energy fragmentation process is determined by the hadronization mechanism and spin structure of hadrons.It can be studied by measuring the polarizations of hyperons and/or vector mesons in e+e- annihilation, in the…
We address optimization of the spin current intensity profile needed to achieve spin torque switching of a nanomagnet. For systems with Ohmic dissipation we prove that the optimal current drives the magnetization along the trajectory, which…
In nuclear-spin-polarization-induced quantum dots the electrons are confined through local nuclear spin polarization. The model electron confinement potential is time-dependent due to the nuclear spin diffusion and relaxation processes. It…
Electric fields represent an ideal means for controlling spins at the nanoscale and, more specifically, for manipulating protected degrees of freedom in multispin systems. Here we perform low-temperature magnetic far-IR spectroscopy on a…
A pure spin current is predicted to occur when an external magnetic field and a linearly inhomogeneous spin-only field are appropriately aligned. Under these conditions (such as originate from nuclear contact hyperfine fields that do not…
The nuclear spin in the vicinity of a nitrogen-vacancy (NV) center possesses of long coherence time and convenient manipulation assisted by the strong hyperfine interaction with the NV center. It is suggested for the subsequent quantum…
We show that the parallel magnetic field-induced increase in the critical electron density for the Anderson transition in a strongly interacting two-dimensional electron system is caused by the effects of exchange and correlations. If the…
We study theoretically the cooling of an ensemble of nuclear spins coupled to the spin of a localized electron in a quantum dot. We obtain a master equation for the state of the nuclear spins interacting with a sequence of polarized…
We consider the problem of determining the spectrum of an electronic spin via polarization transfer to coupled nuclear spins and their subsequent readout. This suggests applications for employing dynamic nuclear polarization (DNP) for…
Nuclear spin polarization is typically generated in GaAs quantum point contacts (QPCs) when an out-of-plane magnetic field gives rise to spin-polarized quantum Hall edge states, and a voltage bias drives transitions between the edge states…