Phys.org February 18, 2019 Transferring information between different types of technology, such as quantum memories and quantum processors has been a persistent challenge. To couple the sound waves with the spins of electrons in the material an international team of researchers (University of Chicago, UC Santa Barbara, Argonne National Laboratory, Japan) built a system with curved electrodes to concentrate the sound waves, like using a magnifying lens to focus a point of light. Using the synchrotron they observed inside the material as the sound waves moved through it. The research reveals the importance of shear strain for future device engineering […]
Category Archives: Spintronics
Overtones can provide faster data communication
Phys.org January 10, 2019 An international team of researchers (Sweden, Portugal) demonstrated how to play and strengthen overtones at the nano level. The researchers have produced spintronic oscillators that strengthen spin wave signals in several steps. When they increased the drive current, the signal showed a sharp jump in frequency: first, from the fundamental frequency of 9 GHz to 14 GHz and then a second jump to 20 GHz. While the wavelength of the fundamental tone is about 500 nanometres, the wavelength of the demonstrated third overtone is as short as 74 nanometres. Future studies on smaller oscillators should be […]
Hybrid qubits solve key hurdle to quantum computing
Phys.org December 28, 2018 Single-spin qubits in semiconductor quantum dots hold promise for universal quantum computation. However, initialization and readout of a qubit is orders of magnitude slower than control. An international team of researchers (Japan, France, Germany, Switzerland) combined slow initializing single-spin qubit called a Loss-DiVincenzo qubit, which has very high control fidelity and a singlet-triplet qubit, which has quick initialization and read out, but quickly becomes decoherent. For the study they combined the two types with a type of quantum gate known as a controlled phase gate, which allowed spin states to be entangled between the qubits in […]
Electronics of the future: A new energy-efficient mechanism using the Rashba effect
Science Daily December 27, 2018 Researchers in Japan using the Rashba effect for generating spin currents in material structures that possess electrons with desirable spin properties. They developed a mechanism to generate a spin current without energy loss from a series of simulations for new quasi-1D materials based on bismuth-adsorbed indium that exhibit a giant Rashba effect. This mechanism does not require an external magnetic field to generate nondissipative spin current. The process would simplify potential spintronic devices and would allow for further miniaturization… read more. Open Access TECHNICAL ARTICLE
Harnessing the power of ‘spin orbit’ coupling in silicon: Scaling up quantum computation
Science Daily December 7, 2018 Coupling spin qubits to electric fields is attractive for simplifying qubit manipulation and couple qubits over long distances. Electron spins in silicon offer long lifetimes, but their weak spin-orbit interaction makes electrical coupling challenging. An international team of scientists (Australia, France) has shown that boron and phosphorus atoms in silicon couple efficiently to electric fields, enabling rapid qubit manipulation and qubit coupling over large distances. Those bound to phosphorus donor qubits revealed a previously unknown coupling of the electron spin to the electric fields typically found in device architectures created by control electrodes. By careful […]
Magnetic topological insulator makes its own magnetic field
Nanowerk November 19, 2018 In experiments, a team of researchers in the US (Rice University, Oak Ridge National Laboratory, NIST) found magnons in CrI3 samples. The structure of the magnon, and the movement of the magnetic wave was quite similar to how electron waves move around graphene. Both graphene and CrI3 contain Dirac points where electrons move just like photons, with zero effective mass, and if they move along the topological edges, there will be no resistance. This is important for dissipationless spintronic applications…read more. Open Access TECHNICAL ARTICLE
A two-atom quantum duet
Science Daily November 9, 2018 While a single spin is easily disrupted, a coupled-spin system can resist decoherence by using a subspace of states that is immune to magnetic field fluctuations. An international team of researchers (South Korea, USA – industry) engineered the magnetic interactions between the electron spins of two spin-1/2 atoms to create a “clock transition” and thus enhance their spin coherence. To construct and electrically access the desired spin structures, they used atom manipulation combined with electron spin resonance. They showed that a two-level system composed of a singlet state and a triplet state is insensitive to […]
Researchers find ferrimagnets could be used to speed up spintronics devices
Phys.org September 25, 2018 For spintronics devices research focused on ferromagnetic materials to stabilize small spin textures and to move them efficiently with high velocities, but ferromagnets show fundamental limits for speed and size. An international team of researchers (USA- MIT, Germany) circumvent these limits using compensated ferrimagnets. Using ferrimagnetic Pt/Gd44Co56/TaOx films they realized a current-driven domain wall motion with a speed of 1.3 km s–1. Both the size and dynamics of the ferrimagnet are in excellent agreement with a simplified effective ferromagnet theory. The research shows using ferrimagnets instead of ferromagnets could theoretically speed up spintronics devices… read more. TECHNICAL ARTICLE
Using spin current to convert mechanical vibrations into electricity
Nanowerk July 20, 2018 Researchers in Japan have designed a nanoscale device that converts mechanical ripples into an electrical current via a spin current. They found that the spin current generated in the second layer was large enough to move magnetic domain walls, which could be used in memory devices. It is still below the spin currents needed, but they could be increased by optimizing the devices. The technology could be used in devices that permit sound waves to pass in one direction but block them in the opposite direction… read more. TECHNICAL ARTICLE
New quantum spin liquid predicted by Nobel Laureate prepared for the first time
Eurekalert March 15, 2018 In 1987 Paul W. Anderson, a Nobel Prize winner in Physics, proposed that high-temperature superconductivity is related to quantum spin liquid. An international team of researchers (Finland, Brazil, Germany, Switzerland, UK, Japan) has developed a new way of tailoring the properties of magnetic materials to produce the superconductor-like quantum spin liquid predicted by Anderson. This achievement is an important step towards building topological quantum computers… read more. Open Access TECHNICAL ARTICLE