Nanowerk February 15, 2021 Researchers in Australia studied the electronic properties of magnesium phthalocyanine (MgPc) sprinkled on a metal surface and demonstrated that the quantum mechanical properties of electrons within the molecules (energy and spatial distribution) are significantly affected by the presence of neighbouring molecules. This effect was observed for intermolecular separation distances of several nanometres. Quantitative analysis of the experimental results and theoretical modelling showed that this interaction was due to mixing between the quantum mechanical orbitals of neighbouring molecules. The molecular orbital mixing leads to significant changes in electron energies and electron distribution symmetries. The long range of […]

# Category Archives: Computing

# Designing customized “brains” for robots

MIT News January 21, 2021 In complex situations robots often do not move quickly because perceiving stimuli and calculating a response takes a lot of computation which limits reaction time. A team of researchers in the US (MIT, Harvard University) used robomorphic computing to bridge the mismatch between a robot’s “mind” and body. Their system creates a customized hardware design to best serve a particular robot’s computing needs. The user inputs the parameters of a robot, the system translates these physical properties into mathematical matrices. These matrices contain many zero values that roughly correspond to movements that are impossible given […]

# Lightmatter’s Mars Chip Performs Neural-Network Calculations at the Speed of Light

IEEE Spectrum August 29, 2020 To perform neural-network calculations faster and more efficiently based on optical computing researchers in the US (industry) have built Mars device which has at its heart a chip that includes an analog optical processor, designed specifically to perform the mathematical operations that are fundamental to neural networks. The key optical processor is shrunk to nanometers and integrated them together on one chip for the purpose of speeding up neural-network calculations. The interferometer splits incoming light into two beams, which then take two different paths. The resulting two beams are then recombined. If the two paths […]

# New approach for controlling qubits via microwave pulses reduces error rates and increases efficiency

Phys.org January 10, 2020 Microwave trapped-ion quantum logic gates avoid spontaneous emission as a fundamental source of decoherence. However, microwave two-qubit gates are still slower than laser-induced gates and hence more sensitive to fluctuations and noise of the motional mode frequency. In order to reduce error rates even further and provide reliable operations much faster researchers in Germany have developed a method where ions are trapped under vacuum by using electric fields above a chip structure. Qubit operations are implemented by sending microwave signals through special conductor loops embedded in the chip structure. Using microwave fields has the advantage that […]

# Reorganizing a computer chip: Transistors can now both process and store information

Science Daily December 9, 2019 Researchers at Purdue University used a semiconductor that has ferroelectric properties. This way two materials become one material so that the interface issues are not a problem. The result is a so-called ferroelectric semiconductor field-effect transistor, built in the same way as transistors currently used on computer chips. The material, alpha indium selenide has ferroelectric properties and a much smaller band gap, making it possible for the material to be a semiconductor without losing ferroelectric properties. The researchers have created a more feasible way to combine transistors and memory on a chip, potentially bringing faster […]

# DARPA uses nature as a muse for new computing model

Defense Systems August 9, 2019 Taking a cue from nature’s efficiency and precision, DARPA is looking for concepts that exploit the interplay between complex dynamical behaviors and intrinsic properties of materials to develop novel computing models for the purpose of tackling current hard computation problems, according to an Aug. 1 solicitation. The two-phase, 18-month program has two technical areas: theory and design, then application development…read more.

# Virtually energy-free superfast computing invented by scientists using light pulses

Science Daily May 15, 2019 An international team of researchers (Germany, USA- UC Santa Barbara, Russia, the Netherlands) utilized the efficient interaction mechanism of coupling between spins and terahertz electric field, which was discovered by the same team. They developed and fabricated a very small antenna on top of the magnet to concentrate and thereby enhance the electric field of light. This strongest local electric field was sufficient to navigate the magnetization of the magnet to its new orientation in just one trillionth of a second without increasing the temperature. Future storage devices would also exploit the excellent spatial definition […]

# Move over, silicon switches: There’s a new way to compute

Science Daily May 8, 2019 A team of researchers in the US (New York University, University of Iowa) has developed a voltage-controlled topological spin switch (VTOPSS) that uses a hybrid topological insulator–magnetic insulator multiferroic material that can implement Boolean logic operations with sub-10-aJ energy per bit. They have developed the theory of its operation, analytic models of its performance metrics, elucidated performance scaling with dimensions and voltage, and benchmarked it against existing spin-based and CMOS devices. Compared with existing spin-based devices the VTOPSS offers 10–70 times lower energy dissipation and 70–1700 times lower energy-delay product. As it will reduce reliance […]

# To Crack the Toughest Optimization Problems, Just Add Lasers

IEEE Spectrum November 27, 2018 Although many complicated optimization problems can be tackled by optimization, there is still a lot of room for improvement in the methods we use to solve a large fraction of optimization problems. Many common optimization problems, including scheduling and route-finding problems, can be easily converted into Ising optimization problems. Researchers at Stanford University are working to build special-purpose optical machines to solve Ising optimization which is finding the lowest energy state of a collection of spins. Key to their prototype system’s ability to map a spin onto a pulse of light is an optical parametric […]

# Effective methods for automated design of complex technical objects and systems

Eurekalert May 18, 2018 To overcome the computational complexity of multicriteria problems researchers in Russia proposed a two-fold approach. First, effective global search algorithms will be used for solving optimization problems. Second, when performing calculations, all the search information received during the calculation will be used to the greatest possible extent. Computational experiments performed by the team shows that the proposed approach makes it possible to reduce more than a hundredfold the amount of required computations when searching for the next effective solution… read more. TECHNICAL ARTICLE