Lifeboat Foundation

Whether for use in safe data encryption, ultrafast calculation of huge data volumes or so-called quantum simulation of highly complex systems: Optical quantum computers are a source of hope for tomorrow’s computer technology. For the first time, scientists now have succeeded in placing a complete quantum optical structure on a chip, as outlined Nature Photonics. This fulfills one condition for the use of photonic circuits in optical quantum computers.

“Experiments investigating the applicability of optical quantum technology so far have often claimed whole laboratory spaces,” explains Professor Ralph Krupke of the KIT. “However, if this technology is to be employed meaningfully, it must be accommodated on a minimum of space.” Participants in the study were scientists from Germany, Poland, and Russia under the leadership of Professors Wolfram Pernice of the Westphalian Wilhelm University of Münster (WWU) and Ralph Krupke, Manfred Kappes, and Carsten Rockstuhl of the Karlsruhe Institute of Technology (KIT).

The light source for the quantum photonic circuit used by the scientists for the first time were special nanotubes made of carbon. They have a diameter 100,000 times smaller than a human hair, and they emit single light particles when excited by laser light. Light particles (photons) are also referred to as light quanta. Hence the term “quantum photonics.”

Continue reading “First quantum photonic circuit with an electrically driven light source” »

Made in America? No, thanks.

Researchers at the Karlsruhe Institute of Technology say they have developed a quantum photonic circuit with an electrically driven light source. Described as a ‘complete quantum optical structure on a chip’, the development is said to fulfil one condition for the use of photonic circuits in optical quantum computers.

“Experiments investigating the applicability of optical quantum technology have often claimed whole laboratory spaces,” said Professor Ralph Krupke. “However, if this technology is to be employed meaningfully, it must be accommodated on a minimum of space.”

The light source for the quantum photonic circuit is carbon nanotubes which emit single particles of light when excited by a laser. Because they emit single photons, carbon nanotubes are attractive as light sources for optical quantum computers.

Continue reading “KIT team develops ‘quantum optical structure on a chip” »

When the quantum computer was imagined 30 years ago, it was revered for its potential to quickly and accurately complete practical tasks often considered impossible for mere humans and for conventional computers. But, there was one big catch: Tiny-scale quantum effects fall apart too easily to be practical for reliably powering computers.

Now, a team of scientists in Japan may have overcome this obstacle. Using laser light, they have developed a precise, continuous control technology giving 60 times more success than previous efforts in sustaining the lifetime of “qubits,” the unit that quantum computers encode. In particular, the researchers have shown that they can continue to create a quantum behavior known as the entangled state—entangling more than one million different physical systems, a world record that was only limited in their investigation by data storage space.

This feat is important because entangled quantum particles, such as atoms, electrons and photons, are a resource of quantum information processing created by the behaviors that emerge at the tiny quantum scale. Harnessing them ushers in a new era of information technology. From such behaviors as superposition and entanglement, quantum particles can perform enormous calculations simultaneously. The report of their investigation appears this week in the journal APL Photonics.

‘Stationary light’ could lead to quantum logic gates – building blocks for quantum computers. Cathal O’Connell reports.

Scientists at the University of Calgary successfully teleported a particle nearly four miles away in a breakthrough experiment that could revolutionize the way computers function.

Researchers used the entanglement property of quantum mechanics, known as “spooky action at a distance,” to teleport a particle. It’s a scientific property not even the renowned Albert Einstein could come to terms with it.

“Being entangled means that the two photons that form an entangled pair have properties that are linked regardless of how far the two are separated,” Dr. Wolfgang Tittel, a physics professor at the University of Calgary who was involved in the research, said in a press statement. “When one of the photons was sent over to City Hall, it remained entangled with the photon that stayed at the University of Calgary. What happened is the instantaneous and disembodied transfer of the photon’s quantum state onto the remaining photon of the entangled pair, which is the one that remained six kilometres [slightly less than 4 miles] away at the university.”

Continue reading “Wonders of Creation: Scientists Use Quantum Mechanics to Teleport Particle 4 Miles” »

When the computer is addressed in many science fiction shows, it often replies in a female-coded voice. From Majel Roddenberry’s Federation computer voice in the Star Trek series to the sentient ship AIs in Andromeda, Killjoys, Dark Matter, Outlaw Star, and Mass Effect, artificial intelligence has been a science fiction regular since at least the 1960’s. There are male-coded AIs as well—J.A.R.V.I.S., Hal, that weird Haley Joel Osment-bot from A.I.—but women have been part of humanity’s relationship with electric computers since the very beginning.

Jennifer S. Light’s article “When Computers Were Women” discusses the ENIAC (Electronic Numerical Integrator and Computer) project during World War II, and how the people doing the actual computational tasks were a group of civilian and military women. The women were actually the “computers,” and were creating a machine that would someday replace them. The concept of the women as the actual computers made me think about how many artificial intelligences, whether in android form or integrated into actual ships, are coded female.

Light’s article also pointed out that history buried these early female computers. Their work was made light of, devalued, and all credit was given to the male inventors of ENIAC, reducing them practically to “ghost in the machine” status. This is where my mind made the connection. So many computer and AI characters are coded female because even layers of sexism and inequality still can’t erase the connection between the first “computers” being women and the task of computing. You can take the woman out of the workplace, but you can’t take the woman out of the machine she helped create.

Researchers from the Graphene Flagship use layered materials to create an all-electrical quantum light emitting diodes (LED) with single-photon emission. These LEDs have potential as on-chip photon sources in quantum information applications.

Atomically thin LEDs emitting one photon at a time have been developed by researchers from the Graphene Flagship. Constructed of layers of atomically thin materials, including transition metal dichalcogenides (TMDs), graphene, and boron nitride, the ultra-thin LEDs showing all-electrical single photon generation could be excellent on-chip quantum light sources for a wide range of photonics applications for quantum communications and networks. The research, reported in Nature Communications, was led by the University of Cambridge, UK.

The ultra-thin devices reported in the paper are constructed of thin layers of different layered materials, stacked together to form a heterostructure. Electrical current is injected into the device, tunnelling from single-layer graphene, through few-layer boron nitride acting as a tunnel barrier, and into the mono- or bi-layer TMD material, such as tungsten diselenide (WSe2), where electrons recombine with holes to emit single photons. At high currents, this recombination occurs across the whole surface of the device, while at low currents, the quantum behaviour is apparent and the recombination is concentrated in highly localised quantum emitters.

Quantum Goddess

Can the University of New South Wales researcher propel Australia first over the finish line in the race to build a reliable quantum computer? Elizabeth Finkel reports.