Related papers: Fast spin rotations by optically controlled geomet…
The absorption of traveling photons resonant with electric dipole transitions of an atomic gas naturally leads to electric dipole spin wave excitations. For a number of applications, it would be highly desirable to shape and coherently…
Spin and orbital freedoms of electrons traveling on spin-resolved quantum Hall edge states (quantum Hall ferromagnets) are maximally entangled. The unitary operations on these two freedoms are hence equivalent, which means one can…
Coherent interactions between spins in quantum dots are a key requirement for quantum gates. We have performed pump-probe experiments in which pulsed lasers emitting at different photon energies manipulate two distinct subsets of electron…
We investigate coherent control of a single electron trapped in a semiconductor quantum dot. Control is enabled with a strong laser field detuned with respect to the electron light-hole optical transitions. For a realistic experimental…
Inverse engineering of electric fields has been recently proposed to achieve fast and robust spin control in a single-electron quantum dot with spin-orbit coupling. In this paper we design, by inverse engineering based on Lewis-Riesenfeld…
A fundamental goal in the manipulation of quantum systems is the achievement of many coherent oscillations within the characteristic dephasing time T2*[1]. Most manipulations of electron spins in quantum dots have focused on the…
Magnetometry is a powerful technique for the non-invasive study of biological and physical systems. A key challenge lies in the simultaneous optimization of magnetic field sensitivity and maximum field range. In interferometry-based…
We describe an interaction mechanism between electron spins in a vertically-stacked double quantum dot that can be used for controlled two-qubit operations. This interaction is mediated by excitons confined within, and delocalized over, the…
We investigate site-controlled In$_{0.25}$Ga$_{0.75}$As quantum dots in (111)B GaAs pyramidal recesses as spin qubits. Combining scanning confocal cryomicroscopy, magneto-photoluminescence studies and resonant excitation, we identify and…
The spin dynamics in a quantum wire with a Rashba spin orbit interaction (SOI) is shown to be controllable via sub-picosecond electromagnetic pulses shaped appropriately. If the light polarization vector is along the wire's direction, the…
Access to the electron spin is at the heart of many protocols for integrated and distributed quantum-information processing [1-4]. For instance, interfacing the spin-state of an electron and a photon can be utilized to perform quantum gates…
We demonstrate the all-optical ultrafast manipulation and read-out of optical transitions in a single negatively charged self-assembled InAs quantum dot, an important step towards ultrafast control of the resident spin. Experiments…
Emerging theoretical concepts for quantum technologies have driven a continuous search for structures where a quantum state, such as spin, can be manipulated efficiently. Central to many concepts is the ability to control a system by…
A single electron spin in a double quantum dot in a magnetic field is considered in terms of a four-level system. By describing the electron motion between the potential minima by spin-conserving tunneling and spin flip caused by a…
We describe an opto-electronic structure in which charge and spin degrees of freedom in electrical gate-defined quantum dots can be coherently coupled to light. This is achieved via electron-electron interaction or via electron tunneling…
Conduction electrons are used to optically polarize, detect and manipulate nuclear spin in a (110) GaAs quantum well. Using optical Larmor magnetometry, we find that nuclear spin can be polarized along or against the applied magnetic field,…
The interaction between spins in coupled quantum dots is revealed in distinct fine structure patterns in the measured optical spectra of InAs/GaAs double quantum dot molecules containing zero, one, or two excess holes. The fine structure is…
We demonstrate control over the spin state of a semiconductor quantum dot exciton using a polarized picosecond laser pulse slightly detuned from a biexciton resonance. The control pulse follows an earlier pulse, which generates an exciton…
Nanofabricated quantum bits permit large-scale integration but usually suffer from short coherence times due to interactions with their solid-state environment. The outstanding challenge is to engineer the environment so that it minimally…
The ability to control spins in semiconductors is important in a variety of fields including spintronics and quantum information processing. Due to the potentially fast dephasing times of spins in the solid state [1-3], spin control…