相关论文: Effects of Nitrogen Quenching Gas on Spin-Exchange…
Optical pumping of an optically thick atomic vapor typically requires a quenching buffer gas, such as N$_{2}$, to prevent radiation trapping of unpolarized photons which would depolarize the atoms. We show that optical pumping of a trace…
We establish the existence of a fundamental limit to the efficiency of spin-exchange optical pumping of 3He nuclei by collisions with spin-polarized alkali-metal atoms. Using accurate ab initio calculations of molecular interactions and…
We have observed depolarization effects when high intensity cold neutron beams are incident on alkali-metal-spin-exchange polarized He-3 cells used as neutron spin filters. This was first observed as a reduction of the maximum attainable…
Excited atomic nitrogen atoms play an important role in plasma formation in hypersonic shock-waves, as happens during spacecraft reentry and other high velocity vehicle applications. In this study, we have thoroughly studied collision…
Dephasing and relaxation of the nuclear spins coupled to the nitrogen-vacancy (NV) center during optical initialization and readout is an important issue for various applications of this hybrid quantum register. Here we present both an…
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…
Several efforts have been made to polarize the nearby nuclear environment of nitrogen vacancy (NV) centers for quantum metrology and quantum information applications. Different methods showed different nuclear spin polarization efficiencies…
Irradiating a semiconductor with circularly polarized light creates spin-polarized charge carriers. If the material contains atoms with non-zero nuclear spin, they interact with the electron spins via the hyperfine coupling. Here, we…
Nuclear spin polarization can be pumped into spin-blocked quantum dots by multiple Landau- Zener passages through singlet-triplet anticrossings. By numerical simulations of realistic systems including approximately $10^7$ nuclear spins…
Spin-blockaded quantum dots provide a unique setting for studying nuclear-spin dynamics in a nanoscale system. Despite recent experimental progress, observing phase-sensitive phenomena in nuclear spin dynamics remains challenging. Here we…
Noble-gas spins feature hours long coherence times owing to their great isolation from the environment, and find practical usage in various applications. However, this isolation leads to extremely slow preparation times, relying on weak…
Using measured spin-transfer rates from alkali atoms to He-3, combined with spin-relaxation rates of the alkali atoms due to He-3 and He-4, it should be possible to differentiate between isotropic and anisotropic spin-exchange. This would…
The periodic optical orientation of electron spins in (In,Ga)As/GaAs quantum dots leads to the formation of electron spin precession modes about an external magnetic field which are resonant with the pumping periodicity. As the electron…
The spin dynamics of localized donor-bound electrons interacting with the nuclear spin ensemble in $n$-doped GaAs epilayers is studied using nuclear spin polarization by light with modulated circular polarization. We show that the observed…
We report a combined experimental and theoretical study of collision-induced dipolar relaxation in a cold spin-polarized gas of atomic nitrogen (N). We use buffer gas cooling to create trapped samples of 14N and 15N atoms with densities…
We report manifestly nonlinear dependence of quantum dot nuclear spin polarization on applied magnetic fields. Resonant absorption and emission of circularly polarized radiation pumps the resident quantum dot electron spin, which in turn…
We present measurements of the optical absorption of K vapor at 795 nm due to the presence of high pressure He gas. The results set a limit on the polarization attainable in hybrid spin-exchange optical pumping of He-3.
The intensity and the giant circular polarization of edge luminescence in a longitudinal magnetic field have been measured in nitrogen alloys GaAsN under circularly polarized pumping. It has been found that these dependences are shifted…
An all-optical scheme to polarize nuclear spins in a single quantum dot is analyzed. The hyperfine interaction with randomly oriented nuclear spins presents a fundamental limit for electron spin coherence in a quantum dot; by cooling the…
We study theoretically the electron spin noise in quantum dots under non-equilibrium conditions caused by the pumping by a train of circularly polarized optical pulses. In such a situation, the nuclear spins are known to adjust in such a…