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We experimentally demonstrate an ultrafast method for preparing spin states of donor-bound electrons in GaAs with single laser pulses. Each polarization state of a preparation pulse has a direct mapping onto a spin state, with bijective correspondence between the Poincar{e}-sphere (for photon polarization) and Bloch-sphere (for spin) state representations. The preparation is governed by a stimulated Raman process and occurs orders of magnitude faster than the spontaneous emission and spin dephasing. Similar dynamics governs our ultrafast optical Kerr detection of the spin coherence, thus getting access to spin state tomography. Experiments with double preparation pulses show an additive character for the preparation method. Utilization of these phenomena is of value for quantum information schemes.
We study the coherence times and perform manipulations on the lowest-energy states of trivalent cerium ion in calcium tungstate crystal. We find the phase memory time reaching 14.2 ${mu}$s and the time of coherent manipulations reaching 0.3 ${mu}$s i
The tailoring of the physical properties of semiconductor nanomaterials by strain has been gaining increasing attention over the last years for a wide range of applications such as electronics, optoelectronics and photonics. The ability to introduce
Optically addressable spins are actively investigated in quantum communication, processing and sensing. Optical and spin coherence lifetimes, which determine quantum operation fidelity and storage time, are often limited by spin-spin interactions, wh
For applications exploiting the valley pseudospin degree of freedom in transition metal dichalcogenide monolayers, efficient preparation of electrons or holes in a single valley is essential. Here, we show that a magnetic field of 7 Tesla leads to a
Spin-orbit coupling fundamentally alters spin qubits, opening pathways to improve the scalability of quantum computers via long distance coupling mediated by electric fields, photons, or phonons. It also allows for new engineered hybrid and topologic