Related papers: Triplet-Singlet Spin Relaxation via Nuclei in a Do…
We report on experiments that quantify the role of a central electronic spin as a relaxation source for nuclear spins in its nanoscale environment. Our strategy exploits hyperpolarization injection from the electron as a means to…
A microscopic theory of spin fluctuations of localized electrons interacting with optically cooled nuclear spin bath has been developed. Since nuclear spin temperature may stay low enough for macroscopically long time, the nuclear spin…
Spin-flip rates in GaAs quantum dots can be quite slow, thus opening up the possibilities to manipulate spin states in the dots. We present here estimations of inelastic spin-flip rates mediated by hyperfine interaction with nuclei. Under…
Spin-dependent transport measurements through a double quantum dot are a valuable tool for detecting both the coherent evolution of the spin state of a single electron as well as the hybridization of two-electron spin states. In this paper,…
Double quantum dots are convenient solid-state platforms to encode quantum information. Two-electron spin states can be conveniently detected and manipulated using strong quantum selection rules based on the Pauli exclusion principle,…
Spin-flips are one of the limiting factors for spin-based information processing. We demonstrate a transport approach for determining the spin-flip rates of a self-assembled InAs double quantum dot occupied by a single electron. In such…
Experimental investigation of nuclear spin effects on the electron spin polarization in singly negatively charged InP quantum dots is reported. Pump-probe photoluminescence measurements of electron spin relaxation in the microsecond…
The coupled nonlinear coordinate and spin dynamics of an electron in a double quantum dot with spin-orbit interaction is studied semiclassically. The system is driven by an electric field with the frequency matching the orbital or the…
A method is proposed for the optical rotation of the spin of an electron in a quantum dot using excited trion states to implement operations up to two orders of magnitude faster than those of most existing proposals. Key ingredients are the…
We study theoretically the spin fluctuations of nuclei in quantum dots. We employ the central spin model which accounts for the hyperfine interaction of the nuclei with the electron spin. We present an analytical solution in the frame of…
We study the decoherence of a single electron spin in an isolated quantum dot induced by hyperfine interaction with nuclei for times smaller than the nuclear spin relaxation time. The decay is caused by the spatial variation of the electron…
A design for a quantum gate performing transformations of a single electron spin is presented. The spin rotations are performed by the electron going around the closed loops in a gated semiconductor device. We demonstrate the operation of…
We suggest a new spin orientation mechanism for localized electrons: $dynamic~electron~spin~polarization~provided~by~nuclear~spin~fluctuations$. The angular momentum for the electrons is gained from the nuclear spin system via the hyperfine…
The spin dynamics in two electron double quantum dots embedded in two dimensional electron gas at the interface between SrTiO$_3$ and LaAlO$_3$ is studied by an exact numerical solution of the time-dependent Schr\"odinger equation, in the…
We investigate the spin relaxation induced by acoustic phonons in the presence of spin-orbit interactions in single electron Si/SiGe lateral coupled quantum dots. The relaxation rates are computed numerically in single and double quantum…
We theoretically model a nuclear-state preparation scheme that increases the coherence time of a two-spin qubit in a double quantum dot. The two-electron system is tuned repeatedly across a singlet-triplet level-anticrossing with…
We polarize nuclear spins in a GaAs double quantum dot by controlling two-electron spin states near the anti-crossing of the singlet (S) and m_S=+1 triplet (T+) using pulsed gates. An initialized S state is cyclically brought into resonance…
Spin is a fundamental property of all elementary particles. Classically it can be viewed as a tiny magnetic moment, but a measurement of an electron spin along the direction of an external magnetic field can have only two outcomes: parallel…
We measure the relaxation rate $W \equiv T_{1}^{-1}$ of a single electron spin in a quantum dot at magnetic fields from 7 T down to 1.75 T, much lower than previously measured. At 1.75 T we find that $T_{1}$ is 170 ms. We find good…
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…