AKA - Diamonds Are For Growing
Image credit: Random twists between layers of crystalline sheets - Neuroncollective dotcom, Daniel Spacek, Pavel Jirak, Chalmers University - 2021 [link]
Rounding up some common topics here, a meditation on the future of computing and ubiquitous intelligence -- quantum lasers, liquid crystals, optical lattices, photon traps, nanosandwiches; it's hard to keep track --
The modern world is fast becoming a wireless, infrared world
June 2020, phys.org
Steerable, narrow infrared beams sending large amounts of data to individual user devices sounds like a solution to the limits of radio-based wifi: Optical wireless communications, which use optical wavelengths over a wide spectral range from a few hundred nanometers to a few micrometers that includes visible and infrared radiation. Ton Koonen and researchers at the Institute for Photonic Integration are designing prototype systems with a capacity of more than two thousand times that of current shared WiFi systems.
via Eindhoven University of Technology, Institute for Photonic Integration: Ton Koonen et al. Ultra-high-capacity wireless communication by means of steered narrow optical beams, Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences (2020). DOI: 10.1098/rsta.2019.0192
Researchers trap electrons to create elusive crystal
Nov 2020, phys.org
Cornell researchers stacked two-dimensional semiconductors [monolayers of tungsten disulfide (WS2) and tungsten diselenide (WSe2)] to create a moiré superlattice structure that traps electrons in a repeating pattern, ultimately forming the long-hypothesized Wigner crystal.
via Cornell University's College of Arts and Sciences, College of Engineering, and the Kavli Institute at Cornell for Nanoscale Science: Yang Xu et al. Correlated insulating states at fractional fillings of moiré superlattices, Nature (2020). DOI: 10.1038/s41586-020-2868-6
Diamonds are not just for jewelry anymore
Dec 2020, phys.org
When it comes to the semiconductor industry, silicon has reigned as king in the electronics field, but it is coming to the end of its physical limits.
To more effectively power the electrical grid, locomotives and even electric cars, Lawrence Livermore National Laboratory (LLNL) scientists are turning to diamond as an ultra-wide bandgap semiconductor.
Diamond has been shown to have superior carrier mobility, break down electric field and thermal conductivity, the most important properties to power electronic devices. It became especially desirable after the development of a chemical vapor deposition (CVD) process for growth of high-quality single crystals.
via Lawrence Livermore National Laboratory: P. Grivickas et al. Carrier recombination and diffusion in high-purity diamond after electron irradiation and annealing, Applied Physics Letters (2020). DOI: 10.1063/5.0028363
Advent of the 3-D diamond valleytronic transistor
Feb 2021, phys.org
Not many people are aware of it, but diamond is actually a wide-bandgap semiconductor with many extremely good properties, such as high thermal conductivity, high breakdown field, high carrier mobilities and chemical inertness. These properties, together with the possibility to synthesize high-purity, single-crystalline diamond make it a very interesting material and a candidate for use in power electronics. The low impurity concentration achieved when fabricating diamond, together with its rigid lattice, cause it to exhibit a uniquely low scattering rate, especially at low temperatures. For this reason, electrons tend to remain in a defined valley and it is then possible to observe valley-polarized electron ensembles, which we have previously proven to exist.
via Uppsala university, Sweden, and Element Six, U.K.: Nattakarn Suntornwipat et al., "A Valleytronic Diamond Transistor: Electrostatic Control of Valley Currents and Charge-State Manipulation of NV Centers", Nano Letters 21, (1), 868-874 (2021), dx.doi.org/10.1021/acs.nanolett.0c04712
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Image credit: Soliton spectral interference patterns - Moritz B. Heindl University of Bayreuth - 2021 |
Scientists create liquid crystals that look a lot like their solid counterparts
Feb 2021, phys.org
May one day lead to new types of smart windows and television or computer displays that can bend and control light.
via University of Colorado at Boulder: Wensink, H.H. et al. Thermally reconfigurable monoclinic nematic colloidal fluids. Nature 590, 268–274 (2021). doi.org/10.1038/s41586-021-03249-0
Using new quantum computing architectures to create time crystals
Nov 2021, phys.org
Just time crystals
via University of California - Berkeley: J. Randall et al, Many-body-localized discrete time crystal with a programmable spin-based quantum simulator, Science (2021). DOI: 10.1126/science.abk0603
A. Kyprianidis et al, Observation of a prethermal discrete time crystal, Science (2021). DOI: 10.1126/science.abg8102
Norman Y. Yao et al, Time crystals in periodically driven systems, Physics Today (2018). DOI: 10.1063/PT.3.4020
Fluorescent nanodiamonds successfully injected into living cells
Mar 2021, phys.org
"Biocampatible" they say.
And for diagnostic purposes.
via Lund University: Elke Hebisch et al. Nanostraw‐Assisted Cellular Injection of Fluorescent Nanodiamonds via Direct Membrane Opening, Small (2021). DOI: 10.1002/smll.202006421
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Image credit: Quantum Computer - MIT Computer Science & Artificial Intelligence Lab - 2022 |
New invention keeps qubits of light stable at room temperature
June 2021, phys.org
Room temperature is always good.
"Right now, we produce the qubits of light at a low rate, one photon per second, while cooled systems can produce millions in the same amount of time. But we believe there are important advantages to this new technology and that we can overcome this challenge in time," Eugene concludes.
via University of Copenhagen: Karsten B. Dideriksen et al, Room-temperature single-photon source with near-millisecond built-in memory, Nature Communications (2021). DOI: 10.1038/s41467-021-24033-8
Team develops quantum simulator with 256 qubits, largest of its kind ever created
Jul 2021, phys.org
"Optical tweezer beams"
via Harvard: Sepehr Ebadi et al, Quantum phases of matter on a 256-atom programmable quantum simulator, Nature (2021). DOI: 10.1038/s41586-021-03582-4
Optical levitation of glass nanosphere enables quantum control
Jul 2021, phys.org
Researchers at ETH Zurich have trapped a tiny sphere measuring a hundred nanometres using light and slowed down its motion to the lowest quantum mechanical state. This technique could help researchers to study quantum effects in macroscopic objects and build extremely sensitive sensors.
via ETH Zurich: Felix Tebbenjohanns et al, Quantum control of a nanoparticle optically levitated in cryogenic free space, Nature (2021). DOI: 10.1038/s41586-021-03617-w
Quantum laser turns energy loss into gain
Jul 2021, phys.org
Laser system that generates highly interactive quantum particles at room temperature.
via The Korea Advanced Institute of Science and Technology: Hyun Gyu Song et al, Room-temperature polaritonic non-Hermitian system with single microcavity, Nature Photonics (2021). DOI: 10.1038/s41566-021-00820-z
Chinese achieve new milestone with 56 qubit computer
Jul 2021, phys.org
2D programable computer called Zuchongzhi
via University of Science and Technology of China: Strong quantum computational advantage using a superconducting quantum processor, arXiv:2106.14734 [quant-ph] arxiv.org/abs/2106.14734
Implementing a 46-node quantum metropolitan area network
Oct 2021, phys.org
Cool and everything, but this part stands out --
To join the network, a new user first had to send a heartbeat frame from their QKD (quantum key distribution) device to the key management server for authentication to then cue the device to generate keys.
via Hefei National Laboratory for Physical Sciences at Microscale and Department of Modern Physics, University of Science and Technology of China: Teng-Yun Chen et al, Implementation of a 46-node quantum metropolitan area network, npj Quantum Information (2021). DOI: 10.1038/s41534-021-00474-3
And: Sebastian Nauerth et al, Air-to-ground quantum communication, Nature Photonics (2013). DOI: 10.1038/nphoton.2013.46
Two Chinese teams claim to have reached primacy with quantum computers
Oct 2021, phys.org
56 cubits
via Hefei National Laboratory for Physical Sciences at the University of Science and Technology of China: Han-Sen Zhong et al, Phase-Programmable Gaussian Boson Sampling Using Stimulated Squeezed Light, Physical Review Letters (2021). DOI: 10.1103/PhysRevLett.127.180502
A potential hangup for quantum computing - Cosmic rays
Dec 2021, Ars Technica
It makes error correction not work, which makes quantum computers not work.
via University of California, Santa Barbara, and Google Quantum AI: Resolving catastrophic error bursts from cosmic rays in large arrays of superconducting qubits. Nature Physics, 2021. DOI: 10.1038/s41567-021-01432-8
Tiny probes could sail to outer planets with the help of low-power lasers
Feb 2022, phys.org
Just space lasers -- I saw this on
Sir Isaac Arthur's show, and it's become the default no-brainer when I try to imagine what space travel will be like. Why carry your fuel with you when you can keep it right here on Earth?
via American Chemical Society: Ho-Ting Tung et al, Low-Power Laser Sailing for Fast-Transit Space Flight, Nano Letters (2022). DOI: 10.1021/acs.nanolett.1c04188
Researchers set record by preserving quantum states for more than 5 seconds
Feb 2022, phys.org
via U.S. Department of Energy's (DOE) Argonne National Laboratory and the University of Chicago: Christopher P. Anderson et al, Five-second coherence of a single spin with single-shot readout in silicon carbide, Science Advances (2022). DOI: 10.1126/sciadv.abm5912
Researchers show how to make a 'computer' out of liquid crystals
Mar 2022, phys.org
Liquid crystals (yes, like LCD screens) are weird because their molecules are ordered like in a diamond crystal, yet they move around. So they have this property -- "the ordered regions bump up against each other and their orientations don't quite match, creating what scientists call "topological defects."
Scientists think these defects can carry information. And it looks like they're right -- they can create "the elementary building blocks of a circuit—gates, amplifiers, and conductors".
via University of Chicago Pritzker School of Molecular Engineering and Argonne National Laboratory: Rui Zhang et al, Logic operations with active topological defects, Science Advances (2022). DOI: 10.1126/sciadv.abg9060
