Nanowerk March 27, 2018 Quantum dot lasers, amplifiers, modulators, and photodetectors epitaxially grown on Si are showing promise for achieving low-cost, scalable integration with silicon photonics. Researchers at UC Santa Barbara made III-V quantum-dot lasers using molecular beam epitaxy. They can run on less power, operate at higher temperatures and scaled down to smaller sizes. They are now testing lasers that can operate at 60 to 80 degrees Celsius, the more typical temperature range of a data center or supercomputer. Replacing the electronic components that connect devices with photonic components could cut energy use by 20 to 75 percent…read more. […]
Tag Archives: Quantum science
Are we quantum computers? International collaboration will investigate the brain’s potential for quantum computation
Phys.org March 27, 2018 QuBrain project at UCSB is a collaborative project among an international team of leading scientists spanning quantum physics, molecular biology, biochemistry, colloid science and behavioral neuroscience to seek explicit experimental evidence to answer whether we might in fact be quantum computers. They will explore neuronal function with state-of-the-art technology from completely new angles. QuBrain has the potential for breakthroughs in the fields of biomaterials, biochemical catalysis, quantum entanglement in solution chemistry and mood disorders in humans, regardless of whether quantum processes indeed take place in the brain… read more.
Controlled coupling of light and matter
Physorg March 6, 2018 To achieve the reabsorption of a photon at room temperature, an international team of researchers (Germany, UK) used a plasmonic nanoresonator, in the form of an extremely narrow slit in a thin gold layer. They controlled the coupling between the resonator and the quantum emitter by implementing a method that allows them to continuously change the coupling and, to switch it on and off in a precise manner. They hope to be able to controllably manipulate the coupling of the quantum dot and the resonator not only by changing their distance, but also through external stimuli—possibly […]
A Preview of Bristlecone, Google’s New Quantum Processor
Google Research Blog March 5, 2018 The guiding design principle for this device is to preserve the underlying physics of our previous 9-qubit linear array technology, which demonstrated low error rates for readout (1%), single-qubit gates (0.1%) and most importantly two-qubit gates (0.6%) as their best result. This device uses the same scheme for coupling, control, and readout, but is scaled to a square array of 72 qubits. They chose a device of this size to be able to demonstrate quantum supremacy in the future, investigate first and second order error-correction using the surface code, and to facilitate quantum algorithm […]
Physicists create new form of light
MIT News February 15, 2018 A team of researchers in the US (MIT, Harvard University, Princeton University, NITS, University of Chicago) has observed groups of three photons interacting and, in effect, sticking together to form a completely new kind of photonic matter. In controlled experiments, the researchers found that when they shone a very weak laser beam through a dense cloud of ultracold rubidium atoms, rather than exiting the cloud as single, randomly spaced photons, the photons bound together in pairs or triplets, suggesting some kind of interaction — in this case, attraction — taking place among them. According to […]
Scientists realize strong indirect coupling in distant graphene-based nanomechanical resonators
Nanowerk January 28, 2018 The main problem using nanomechanical resonators as information carriers is the realization of tunable phonon interaction at long distance. An international team of researchers (China, USA) reports the experimental observation of strong indirect coupling between separated mechanical resonators in a graphene-based electromechanical system. The coupling is mediated by a far-off-resonant phonon cavity through virtual excitations via a Raman-like process. By controlling the resonant frequency of the phonon cavity, the indirect coupling can be tuned in a wide range. The results may lead to the development of gate-controlled all-mechanical devices and open the possibility of long-distance quantum […]