Bose-Einstein condensate tagged posts

Using ultracold atoms and laser light, researchers recreated the behavior of a Josephson junction—an essential component of quantum computers and voltage standards. The appearance of Shapiro steps in this atomic system reveals a deep universality in quantum physics and makes elusive microscopic effects visible for the first time.

Josephson junctions play a central role in modern physics and technology. They enable extremely precise measurements, define the international standard for electrical voltage, and serve as essential components inside many quantum computers...

The wavelength of emitted light grows, that is, the energy decreases, along the gold nanorod array. A Bose-Einstein condensate forms when an energy minimum of the lattice is reached. Credit: Aalto University / Tommi Hakala and Antti Paraoanu

Nearly a hundred years ago, Albert Einstein and Satyendra Nath Bose predicted that quantum mechanics can force a large number of particles to behave in concert as if they were only a single particle. The phenomenon is called Bose-Einstein condensation, and it took until 1995 to create the first such condensate of a gas of alkali atoms. Although Bose-Einstein condensation has been observed in several systems, the limits of the phenomenon need to be pushed further: to faster timescales, higher temperatures, and smaller sizes...

The electron (blue) orbits the nucleus (red) — and its orbit encloses many other atoms of the Bose-Einstein-condensate (green). Credit: TU Wien

Scientists have provided proof for a new state of matter: an electron orbits a nucleus at a great distance, while many other atoms are bound inside the orbit. What is inside an atom, between the nucleus and the electron? Usually there is nothing, but why could there not be other particles too? If the electron orbits the nucleus at a great distance, there is plenty of space in between for other atoms. A “giant atom” can be created, filled with ordinary atoms. All these atoms form a weak bond, creating a new, exotic state of matter at cold temperatures, referred to as “Rydberg polarons.”

A team of researchers has now presented this state of matter in...

Hypothetically, matter can have negative mass in the same sense that an electric charge can be either negative or positive. With negative mass, if you push something, it accelerates toward you. Forbes said, “It looks like the rubidium hits an invisible wall.” (stock image). Credit: © ktsdesign / Fotolia

Experimental technique can help probe phenomena in astrophysics and cosmology. Washington State University physicists have created a fluid with negative mass, which is exactly what it sounds like. Push it, and unlike every physical object in the world we know, it doesn’t accelerate in the direction it was pushed. It accelerates backwards...