#quantum bits

Quantum Criticality Could Be a Boon for Qubit Designers

Physicists studying the strange behavior of metal alloys called heavy fermions have made a surprising discovery that could be useful in safeguarding the information stored in quantum bits, or qubits, the basic units of encoded information in quantum computers.

In a study in the Proceedings of the National Academy of Sciences, researchers from Rice University and the Vienna University of…

Regular old quantum teleportation wasn’t enough for scientists. So they’ve kicked it up a notch.

Previously, physicists had teleported qubits, or quantum bits of information. Just as a standard bit in a desktop computer has two possible values, 0 or 1, a qubit has two possible states. Now scientists have moved on, reporting in the Aug. 16 Physical Review Letters that they’ve teleported qutrits, which have three possible states. Both qubits and qutrits have the weird quantum property of being able to exist in multiple states at once. But while a qubit can represent 0 and 1 at the same time, a qutrit can be a combination of 0, 1 and 2.

In quantum teleportation, rather than sending objects from one place to another in Star Trek fashion, the properties of a quantum particle are transferred to another, distant particle (SN Online: 7/7/17). Until now, those properties could only be binary. For example, a particle of light, or photon, could be made to take one of two paths through a device — or both at once — and the information about which paths the particle took could be transferred to another particle.

In the new study, the team teleported the properties of photons that had three possible states: The particles could have taken three different paths — or all three at once. Because qutrits carry more information that qubits, the technique could be a boon for quantum communication. Scientists are preparing for a future quantum internet that would use quantum particles to securely send information (SN: 10/15/16, p. 13).

Researchers have also previously teleported two different properties of a particle at once (SN: 3/21/15, p. 14). By improving and combining these techniques, scientists might eventually be able to completely reproduce a particle in another location.

Schrödinger’s Cat with 20 Qubits

Dead or alive, left-spinning or right-spinning – in the quantum world particles such as the famous analogy of Schrödinger’s cat can be all these things at the same time. An international team, including researchers from several leading American universities, together with experts from Forschungszentrum Jülich, have now succeeded in transforming 20 entangled quantum bits into such a state of…

Silicon provides means to control quantum bits for faster algorithms

---No matter how much I read articles so far on quantum bits--qubits--and quantum chips and computing, they basically still sound like gibberish to me.  Even though I understand the concept of the cat being both dead and alive until it’s observed, I still can’t really yet grasp how they are actually making useful electronics and physics based on these concepts.  I’d love to learn, but so far, reading things about it hasn’t been helping.  Although it is of course fascinating that something so seemingly strange can exist.

Quantum teleportation on a chip

The core circuits of quantum teleportation, which generate and detect quantum entanglement, have been successfully integrated into a photonic chip by an international team of scientists from the universities of Bristol, Tokyo, Southampton and NTT Device Technology Laboratories. These results pave the way to developing ultra-high-speed quantum computers and strengthening the security of…