Researchers Develop Rice-Sized Laser That Can Boost Quantum Computing Researchers have developed a microwave laser or maser, which will help the world to take a major step towards quantum computing.

Princeton University researchers developed a laser the size of a grain of rice, while investigating the use of semiconductor material fragments as components for quantum computing. The study was started to explore the quantum dots, and not lasers. Quantum dots act like single atoms, as components for quantum computers. The maser is a tiny, rice grain sized laser that is powered by a single electron from the artificial atoms called quantum dots.

Jason Petta, an associate professor of physics at Princeton and the lead author of the study, said, �It is basically as small as you can go with these single-electron devices.�

The discovery will boost the ongoing efforts of scientists across the world to use semiconductor materials to build quantum-computing systems.

�I consider this to be a really important result for our long-term goal, which is entanglement between quantum bits in semiconductor-based devices,� said Jacob Taylor, an adjunct assistant professor at the Joint Quantum Institute at the University of Maryland-National Institute of Standards and Technology.

The researcher added that they were initially interested in exploring the use of quantum dots together. That means two quantum dots joined together as quantum bits or qubits. Qubits are the basic unit of information in quantum computing.

�We designed dots to emit photons when single electrons jump from a higher to a lower energy level across the double dot. It is like a line of people crossing a wide stream by leaping onto a rock so small that it can only hold one person. They are forced to cross the stream one at a time. These double quantum dots are zero-dimensional as far as the electrons are concerned � they are trapped in all three spatial dimensions,� explained Petta.

A single electron trapped in a semiconductor nanostructure can form the most basic of building blocks for a quantum computer. However, before practical quantum computers can be realized, scientists need to develop a scalable architecture that allows full control over individual electrons in computational arrays.

The findings were published in the Science journal.