Related papers: Controlling photon polarisation with a single quan…
For a general-form polarization biphoton qutrit, physically corresponding to a pair of arbitrarily polarized photons in a single frequency and wavevector mode, we explicitly find polarization Schmidt modes. A simple method is suggested for…
Single electron spins in semiconductor quantum dots (QDs) are a versatile platform for quantum information processing, however controlling decoherence remains a considerable challenge. Recently, hole spins have emerged as a promising…
A hole spin is a potential solid-state q-bit, that may be more robust against nuclear spin induced dephasing than an electron spin. Here we propose and demonstrate the sequential preparation, control and detection of a single hole spin…
Single-photon sources play a key role in photonic quantum technologies. Semiconductor quantum dots can emit indistinguishable single photons under resonant excitation. However, the resonance fluorescence technique typically requires…
Selective coherence control and electrically mediated exchange coupling of single electron spin between triplet and singlet states using numerically derived optimal control of proton pulses is demonstrated. We obtained spatial confinement…
Controlling large-scale many-body quantum systems at the level of single photons and single atomic systems is a central goal in quantum information science and technology. Intensive research and development has propelled foundry-based…
Due to their ability to strongly modify the local electromagnetic (EM) field through the excitation of surface plasmon polaritons (SPPs), plasmonic nanostructures have been often used to reshape the emission direction and enhance the…
Spin manipulation in coupled quantum dots is of interest for quantum information applications. Control of the exchange interaction between electrons and holes via an applied electric field may provide a promising technique for such spin…
Electrically controlled photonic circuits hold promise for information technologies with greatly improved energy efficiency and quantum information processing capabilities. However, weak nonlinearity and electrical response of typical…
We show that detuned optical pulse trains with a modest spectral width can polarize nuclear spins in InAs quantum dots. The pulse bandwidth is large enough to excite a coherent superposition of both electron spin eigenstates in these…
We present a theory of the optical control of the spin of an electron in an InAs quantum dot. We show how two Raman-detuned laser pulses can be used to obtain arbitrary single-qubit rotations via the excitation of an intermediate trion…
We present a quantum mechanical theory of optically induced dynamic nuclear polarization applicable to quantum dots and other interacting spin systems. The exact steady state of the optically driven coupled electron-nuclear system is…
A classical circularly polarized electromagnetic wave carries angular momentum, and represents the classical limit of a photon, which carries quantized spin. It is shown that a very similar picture of a circularly polarized coherent wave…
Controlling the depolarization of light is a long-standing open problem. In recent years, many demonstrations have used the polarization of single photons to encode quantum information. The depolarization of these photons is equivalent to…
We study the absorption and emission polarization of single semiconductor quantum dots in semiconductor nanowires. We show that the polarization of light absorbed or emitted by a nanowire quantum dot strongly depends on the orientation of…
Electron spins and photons are complementary quantum-mechanical objects that can be used to carry, manipulate and transform quantum information. To combine these resources, it is desirable to achieve the coherent coupling of a single spin…
Topological insulators are characterized by Dirac cone surface states with electron spins aligned in the surface plane and perpendicular to their momenta. Recent theoretical and experimental work implied that this specific spin texture…
We use a microwave field to control the quantum state of optical photons stored in a cold atomic cloud. The photons are stored in highly excited collective states (Rydberg polaritons) enabling both fast qubit rotations and control of…
The spin states of electrons confined in semiconductor quantum dots form a promising platform for quantum computation. Recent studies of silicon CMOS qubits have shown coherent manipulation of electron spin states with extremely high…
We demonstrate for the first time that a matter physical two level system, a qubit, can be fully controlled using one ultrafast step. We show that the spin state of an optically excited electron, an exciton, confined in a quantum dot, can…