How did Lene Hau slow down light?

How did Lene Hau slow down light?

In 1999, she led a Harvard University team who, by use of a Bose–Einstein condensate, succeeded in slowing a beam of light to about 17 metres per second, and, in 2001, was able to stop a beam completely.

How does Bose Einstein Condensate work?

A Bose-Einstein condensate is a group of atoms cooled to within a hair of absolute zero. When they reach that temperature the atoms are hardly moving relative to each other; they have almost no free energy to do so. At that point, the atoms begin to clump together, and enter the same energy states.

How do you slow down a light?

A new technique slows down light in a crystal by simply shining a laser on it and varying an applied voltage. When it comes to transmitting information quickly between data processors, photons do better than electrons. For a trivial reason: electrons can’t beat the speed of light.

What is the speed of light in Bose-Einstein condensate?

The most intriguing property of BECs is that they can slow down light. In 1998 Lene Hau of Harvard University and her colleagues slowed light traveling through a BEC from its speed in vacuum of 3 × 108 metres per second to a mere 17 metres per second, or about 38 miles per hour.

Who slowed light?

In 1998, Danish physicist Lene Vestergaard Hau led a combined team from Harvard University and the Rowland Institute for Science which realized much lower group velocities of light. They succeeded in slowing a beam of light to about 17 meters per second,.

How are Bose Einstein condensate formed?

In condensed matter physics, a Bose–Einstein condensate (BEC) is a state of matter that is typically formed when a gas of bosons at low densities is cooled to temperatures very close to absolute zero (−273.15 °C or −459.67 °F).

Why is speed of light slower in water?

When light is transmitted through matter, it is acts absorbed and re-emitted every time it runs into a particle. In between the particles it does travel at the speed of light, but the absorption and emission takes a bit of time. With a liquid the particles are close together, so that really slows it down.

Why would scientists want to slow light down?

Significance of the research Slow light has potential applications in telecommunications because it could lead to a more orderly traffic flow in networks. Like cars slowing down or speeding up to negotiate an intersection, packets of information are better managed if their transmission speed is changeable.

What is the Bose-Einstein condensate?

Eric A. Cornell of the National Institute of Standards and Technology and Carl E. Wieman of the University of Colorado at Boulder led a team of physicists at JILA, a joint institute of NIST and CU-Boulder, in a research effort that culminated in 1995 with the creation of the world’s first Bose-Einstein condensate—a new form of matter.

How can we slow down light?

It’s possible to slow light down by making it interact with matter and, in a sense, converting photons to something with mass. That’s one way to understand what Lene Hau and colleagues at the Rowland Institute of Science did in 1999 when they slowed light to 17 miles per hour in a Bose Einstein Condensate (BEC) made of ultracold sodium atoms.

How do lasers slow down light?

The first laser sets up a “quantum interference” such that the moving light beams of the second laser interfere with each other. When everything is set up just right, the light can be slowed by a factor of 20 million. The process is described in detail in the Feb. 18 issue of the scientific journal Nature.

What is the difference between the Bose-Einstein and Jin-DeMarco experiments?

While the Bose-Einstein experiments used one class of quantum particles known as bosons, Jin and DeMarco cooled atoms that are fermions, the other class of quantum particles found in nature. This was important to physicists because the basic building blocks of matter—electrons, protons and neutrons — are all fermions.