In analogy to the coupling of atoms into molecules, the authors fuse colloidal semiconductor nanocrystals into quantum dot dimers. These nanocrystal ‘molecules’ exhibit significant quantum coupling effects, making them promising for applications in devices and potential quantum technologies.
When the researchers used their system to measure the qubits’ state, they achieved an accuracy of 98 percent, exactly the same as when they carried out the measurement using a conventional electrical cable.
The authors acknowledge that work is already underway to try and reduce the heat produced by current approaches, including the development of thinner wires, proposals to replace wires with superconducting cables, or a process called multiplexing that makes it possible to send many signals over the same cable simultaneously.
But optical fiber is a well-established technology, and is already replacing electrical wires in many areas of computing thanks to its ability to carry far more data. The authors also point out that components used in this experiment were designed to work at room temperature, so optimizing them for cryogenic temperatures could provide significant performance gains.
CLEVELAND, Ohio — The Cleveland Clinic and IBM have entered a 10-year partnership that will install a quantum computer — which can handle large amounts of data at lightning speeds — at the Clinic next year to speed up medical innovations.
The Discovery Accelerator, a joint Clinic-IBM center, will feature artificial intelligence, hybrid cloud data storage and quantum computing technologies. A hybrid cloud is a data storage technology that allows for faster storage and analysis of large amounts of data.
The partnership will allow Clinic researchers to use the advanced tech in its new Global Center for Pathogen Research and Human Health for research into genomics, population health, clinical applications, and chemical and drug discovery.
A force is something which tends to change the state of rest or state of motion, or size, shape, the direction of motion of a body, etc… There are four fundamental forces: gravitational, electromagnetic, strong nuclear and weak nuclear forces. These forces are responsible for all possible interactions that can take place in this universe, from planets orbiting a star to protons and neutrons confined in the nucleus of an atom. In classical physics, the assumption was that an imaginary field exists, through which a force can be transmitted. But with the advent of quantum mechanics, this idea was changed radically. A field exists, but that is a quantum field. The field vibrates gently, and these vibrations give rise to particles and their corresponding antiparticle partners, i.e., particles with opposite charge. But these particles can exist for a limited amount of time. What gives rise to forces then? Particles called bosons. Bosons, named after Indian physicist Satyendra Nath Bose, are particles, the exchange of which give rise to forces. Bosons, along with the fermions (which make up matter), are referred to as elementary particles [1].
In quantum mechanics, energy can be temporarily ‘borrowed’ from a particle. But, as per Heisenberg’s uncertainty principle, the greater the amount of energy you ‘borrow’, the sooner you must return it [2].
Bacteria have been found exploiting quantum physics to survive.
Oxygen is life to animals like us. But for many species of microbe, the smallest whiff of the highly reactive element puts their delicate chemical machinery at risk of rusting up.
The photosynthesizing bacterium Chlorobium tepidum has evolved a clever way to shield its light-harvesting processes from oxygen’s poisonous effects, using a quantum effect to shift its energy production line into low gear.
Once particularly useful future application, according to Harvard Business Review, will be the potential development of new drugs, a task it is “uniquely suited for” because it would operate on the same laws of quantum physics as the molecules it is simulating.
And so, Abu Dhabi has joined the community of nations endeavouring to accomplish this next step in human history.
The Advanced Technology Research Council is building the computer at its Quantum Research Centre labs in Abu Dhabi, in collaboration with Barcelona-based Qilimanjaro Quantum Tech.
A new class of quantum dots deliver a stable stream of single, spectrally tunable infrared photons under ambient conditions and at room temperature, unlike other single photon emitters. This breakthrough opens a range of practical applications, including quantum communication, quantum metrology, medical imaging and diagnostics, and clandestine labeling.
“The demonstration of high single-photon purity in the infrared has immediate utility in areas such as quantum key distribution for secure communication,” said Victor Klimov, lead author of a paper published today in Nature Nanotechnology by Los Alamos National Laboratory scientists.
The Los Alamos team has developed an elegant approach to synthesizing the colloidal-nanoparticle structures derived from their prior work on visible light emitters based on a core of cadmium selenide encased in a cadmium sulfide shell. By inserting a mercury sulfide interlayer at the core/shell interface, the team turned the quantum dots into highly efficient emitters of infrared light that can be tuned to a specific wavelength.
The torsion balance contains a rigid balance beam suspended by a fine thread as an ancient scientific instrument that continues to form a very sensitive force sensor to date. The force sensitivity is proportional to the lengths of the beam and thread and inversely proportional to the fourth power of the diameter of the thread; therefore, nanomaterials that support the torsion balances should be ideal building blocks. In a new report now published on Science Advances, Lin Cong and a research team in quantum physics, microelectronics and nanomaterials in China have detailed a torsional balance array on a chip with the highest sensitivity level. The team facilitated this by using a carbon nanotube as the thread and a monolayer graphene coated with aluminum films as the beam and mirror. Using the experimental setup, Cong et al. measured the femtonewton force exerted by a weak laser. The balances on the chip served as an ideal platform to investigate fundamental interactions up to zeptonewton in accuracy.
A modern role for ancient scientific instruments
The torsion pendulum is an ancient scientific instrument used to discover Coulomb’s law in 1785 and to determine the density of Earth in 1798. The instrument is useful across a range of applications including existing scientific explorations of precisely determining the gravitational constant. The most efficient method to achieve high sensitivity in the setup is by reducing the diameter of the suspension thread as much as possible. For instance, in 1931, Kappler et al. used a centimeters-long thread to develop a highly sensitive torsion balance to set a record for a hitherto unattained intrinsic force sensitivity. At present, carbon nanotubes form one of the strongest and thinnest materials known. In this work, the team synthesized ultra-long carbon nanotubes (CNTs) and large-area graphene to substantially increase the lengths of the balance beam and suspension thread to significantly improve the sensitivity of the instrument.
Bright semiconductor nanocrystals known as quantum dots give QLED TV screens their vibrant colors. But attempts to increase the intensity of that light generate heat instead, reducing the dots’ light-producing efficiency.
A new study explains why, and the results have broad implications for developing future quantum and photonics technologies where light replaces electrons in computers and fluids in refrigerators, for example.
In a QLED TV screen, dots absorb blue light and turn it into green or red. At the low energies where TV screens operate, this conversion of light from one color to another is virtually 100% efficient. But at the higher excitation energies required for brighter screens and other technologies, the efficiency drops off sharply. Researchers had theories about why this happens, but no one had ever observed it at the atomic scale until now.