National Ignition Facility’s laser energy is converted into x-rays inside the hohlraum, which then compress a fuel capsule until it implodes, creating a high temperature, high pressure plasma in an undated photograph at Lawrence Livermore National Laboratory federal research facility in Livermore, California, U.S.
| Photo Credit: Reuters

Questions:

1. In 1975, X, Hans Georg Dehmelt, Theodor Hansch, and Arthur Schawlow proposed the possibility of laser cooling atoms, and X and others validated it by demonstrating it three years later. Name X, who won a part of the physics Nobel Prize in 2012.

2. Y was one of the Nobel Prize for physics in 1997 “for the development of methods to cool and trap atoms with laser light”. Thus, he became the first Nobel Laureate born in an Arab country. Y is famous for developing a variant of laser cooling called ________ cooling. Fill in the blank with the name of a cursed hero in Greek mythology.

3. A simple laser cooling technique is called _______ cooling. Here (very simply speaking), laser light is shined on oncoming atoms. The atoms absorb photons from the laser – more so due to the _______ effect – and slow down in that direction. Fill in the blank with the same name. Hint: the effect is also experienced when one observes trains.

4. Name the little-known Indian physicist, and a doctoral student of C.V. Raman, who discovered many of the principles underlying laser cooling. Notably, he discovered the geometric phase – a generalised form of which is today called the Berry phase, for Michael Berry.

5. Name the device used in atomic and molecular physics research to trap atoms, including electrically neutral ones. It does this using laser cooling and a non-uniform magnetic field, and can slow some atoms from more than ~100 m/s to ~0.1 m/s.

Visual:

This illustration shows an apparatus that uses precisely tuned light beams to hold and rotate a cell. Name the technology in which such laser light is used to hold and move atoms.

Answers:

1. David Wineland

2. Claude Cohen-Tannoudji

3. Doppler cooling

4. Shivaramakrishnan Pancharatnam

5. Magneto-optical trap

Visual: Optical tweezers