Ordered quantum dot molecules are grown by a modified MBE growth using thin-capping and regrowth processes. This technique yields QDs which are uniform and aligned along [11̄0] directions. This paper presents an attempt to group 4-5 dots per each quantum dot molecule, in order to form a physical structure that can function as quantum cellular automata, giving rise to the possibility of developin...

ABSTRACT This paper describes new quantum-dot circuits that measure a Hamming distance by using the Coulomb repulsion effect between quantum dots. Measuring similarity between patterns expressed by a Hamming distance is a basic function for various information processing. Quantum dot structures realizing these circuits are also proposed, which will be constructed by using the well-controlled na...

: Quantum-dot cellular automata are an interesting nanoscale computing paradigm. The introduction of the ternary quantum-dot cell enabled ternary computing, and with the recent development of a ternary functionally complete set of elementary logic primitives and the ternary memorizing cell design of complex processing structures is becoming feasible. The specific nature of the ternary quantum-d...

We propose a quantum dot qubit architecture that has an attractive combination of speed and fabrication simplicity. It consists of a double quantum dot with one electron in one dot and two electrons in the other. The qubit itself is a set of two states with total spin quantum numbers S(2)=3/4 (S=1/2) and S(z)=-1/2, with the two different states being singlet and triplet in the doubly occupied d...

For the application of colloidal semiconductor quantum dots in optoelectronic devices, for example, solar cells and light-emitting diodes, it is crucial to understand and control their charge transport and recombination dynamics at high carrier densities. Both can be studied in ambipolar, light-emitting field-effect transistors (LEFETs). Here, we report the first quantum dot light-emitting tran...

Transient nonlinear optical spectroscopy, performed on excitons confined to single GaAs quantum dots, shows oscillations that are analogous to Rabi oscillations in two-level atomic systems. This demonstration corresponds to a one-qubit rotation in a single quantum dot which is important for proposals using quantum dot excitons for quantum computing. The dipole moment inferred from the data is c...

Strongly coupled quantum dot-cavity systems provide a non-linear configuration of hybridized light-matter states with promising quantum-optical applications. Here, we investigate the coherent interaction between strong laser pulses and quantum dot-cavity polaritons. Resonant excitation of polaritonic states and their interaction with phonons allow us to observe coherent Rabi oscillations and Ra...

The widely popular class of quantum-dot molecular labels could so far not be utilized as standard fluorescent probes in STED (stimulated emission depletion) nanoscopy. This is because broad quantum-dot excitation spectra extend deeply into the spectral bands used for STED, thus compromising the transient fluorescence silencing required for attaining super-resolution. Here we report the discover...

The self-assembled quantum dot structure is an interesting topic for physical investigation of zero-dimensional system. Due to the low-dimensional confinement effect, the Ge-on-Si quantum dot structure is expected to demonstrate novel optoelectronic properties that can be applied to develop Sibased technology competitive with traditional optoelectronic materials such as III-V compounds. In addi...