Category Physics

Demonstration of scrambling in quantum computer shows how to resurrect ‘lost’ information. Physicists have used a seven-qubit quantum computer to simulate the scrambling of information inside a black hole, heralding a future in which entangled quantum bits might be used to probe the mysterious interiors of these bizarre objects.

Scrambling is what happens when matter disappears inside a black hole...

Scientists have found a way to build the ‘opposite’ of a laser – a device that absorbs a specific light wave perfectly. This can be done even in complicated systems, in which waves are scattered randomly, and has many technological applications.

At TU Wien (Vienna), a method has now been developed to make use of this effect, even in very complicated systems in which light waves are randomly scattered in all directions. The method was developed in Vienna with the help of computer simulations, and confirmed by experiments in cooperation with the University of Nice. This opens up new possibilities for all technical disciplines that have to do with wave phenomena. The new method has now been published in the journal Nature.

“Every day we are de...

Researchers observe an unusual quantum Hall effect in the old 3D material. Researchers at The University of Manchester in the UK, led by Dr Artem Mishchenko, Prof Volodya Fal’ko and Prof Andre Geim, have discovered the quantum Hall effect in bulk graphite – a layered crystal consisting of stacked graphene layers. This is an unexpected result because the quantum Hall effect is possible only in so-called 2D systems where electrons’ motion is restricted to a plane and must be disallowed in the perpendicular direction...

Scientists have developed a faster way to read information out of qubits, the basic building blocks of a quantum computer. The potential computing revolution that quantum computers have long promised is based on their weird property called superposition. Namely, qubits can take both logical states 0 and 1 simultaneously, on top of any value in between. By mastering superpositions of the whole quantum memory, quantum computers can quickly solve problems that would require too much computing time from regular computers working with simply 0s and 1s.

However, qubits are sensitive, and currently hold quantum information for less than a millisecond ...