Related papers: Low-Frequency Excitation of Singlet-Triplet Transi…
We observe mixing between two-electron singlet and triplet states in a double quantum dot, caused by interactions with nuclear spins in the host semiconductor. This mixing is suppressed by applying a small magnetic field, or by increasing…
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…
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…
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…
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…
We introduce a broadly applicable technique to create nuclear spin singlet states in organic molecules and other many-atom systems. We employ a novel pulse sequence to produce a spin-lock induced crossing (SLIC) of the spin singlet and…
Coupled pairs of spin-1/2 nuclei support one singlet state and three triplet states. In many circumstances the nuclear singlet order, defined as the difference between the singlet population and the mean of the triplet populations, is a…
We consider nuclear spin dynamics in a two-electron double dot system near the intersection of the electron spin singlet $S$ and the lower energy component $T_{+}$ of the spin triplet. The electron spin interacts with nuclear spins and is…
Recently, Pang et al reported a novel polarization transfer scheme applicable to three-spin systems, whereby a rotating-frame NMR analogue of the cross effect could transfer polarization between; e.g., two 13Cs and an 15N in a single…
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…
A quasi-classical theoretical description of polarization and relaxation of nuclear spins in a quantum dot with one resident electron is developed for arbitrary mechanisms of electron spin polarization. The dependence of the…
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…
The nuclear pairing condensate is expected to change character from spin-singlet to spin-triplet when the nucleus is very large and the neutron and proton numbers $Z,N$ are equal. We investigate the transition between these two phases…
Nuclear spins and paramagnetic centers in a solid randomly group to form clusters featuring nearly-degenerate, hybrid states whose dynamics are central to processes involving nuclear spin-lattice relaxation and diffusion. Their…
Linearly polarized light tuned slightly below the optical transition of the negatively charged exciton (trion) in a single quantum dot causes the spontaneous nuclear spin polarization (self-polarization) at a level close to 100%. The…
Radical pair recombination reactions are known to be sensitive to the application of both low and high magnetic fields. The application of a weak magnetic field reduces the singlet yield of a singlet-born radical pair, whereas the…
We have evaluated hyperfine-induced electron spin dynamics for two electrons confined to a double quantum dot. Our quantum solution accounts for decay of a singlet-triplet correlator even in the presence of a fully static nuclear spin…
We study two-electron states confined in two coupled quantum dots formed by a short-range potential in a two-dimensional topological insulator. It is shown that there is a fairly wide range of the system parameters, where the ground state…
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…
[Background] Nuclear pairing is a well-established many-body correlation, particularly among like particles in a spin-singlet state. However, the strength of spin-triplet proton-neutron (pn) pairing in nuclei has remained a long-standing…