Ancient Namibian Gemstone Could Help Create Special Quantum Computers In Future, New Study Finds

The scientists used a naturally mined cuprous oxide (Cu2O) gemstone from Namibia to produce Rydberg polaritons, which are the largest particles of light and matter ever created.

Cuprous oxide crystal – the mined crystal from Namibia used for making Rydberg polaritons | Credit: University of St Andrews

New Delhi: A special form of light made using an ancient Namibian gemstone could lead to the creation of new light-based quantum computers, a new study has found. These quantum computers could help solve long-held scientific mysteries. 

The study, led by researchers at the University of St Andrews, Scotland, in collaboration with scientists at Harvard University in the United States, Macquarie University in Australia, and Aarhus University in Denmark, was recently published in the journal Nature Materials.

The scientists used a naturally mined cuprous oxide (Cu2O) gemstone from Namibia to produce Rydberg polaritons, which are the largest particles of light and matter ever created.

What Are Rydberg Polaritons?

Rydberg polaritons switch continually from light to matter and back again, and in these hybrid particles, light and matter are like two sides of a coin. According to the study, the matter side is what makes polaritons interact with each other. Polaritons are hybrid particles made up of a photon strongly coupled to an electric dipole, which is a separation of positive and negative charges.

Quantum Simulators – A Special Type Of Quantum Computer

The interaction of polaritons amongst one another is important because this is what allows the creation of quantum simulators, a special type of quantum computer, the study said. 

In a quantum simulator, information is stored in quantum bits, which, unlike binary bits in classical computers, can take any value between 0 and 1. 

The binary bits in classical computers can only be 0 or 1. 

The quantum simulators, therefore, can store much more information and perform several processes simultaneously. 

What Scientific Mysteries Can Quantum Simulators Solve?

With the help of this capability, quantum simulators can solve important mysteries of physics, chemistry, and biology. For instance, quantum simulators can determine how to make high-temperature superconductors for high speed trains, how cheaper fertilisers could be made to solve global hunger, or how proteins fold. If quantum simulators can discover the mechanism behind folding of proteins, it will become easier to produce more effective drugs.

In a statement issued by the University of St Andrews, Project lead Dr Hamid Ohadi said that making a quantum simulator with light is the holy grail of science. He said that the researchers have taken a huge leap towards this by creating Rydberg polaritons, the key ingredient of it. 

How Were Rydberg Polaritons Created?

The scientists trapped light between two highly reflective mirrors to create Rydberg polaritons. They thinned a cuprous oxide crystal from a stone mined in Namibia. It was polished to a 30-micrometre-thick slab, which is thinner than a strand of human hair.

Then, the researchers sandwiched the crystal between the two mirrors to make Rydberg polaritons 100 times larger than ever demonstrated before.

Dr Sai Kiran Rajendran, one of the lead authors of the study, said that the challenge was to make Rydberg polaritons that exist in an extremely narrow colour range.

The researchers are currently refining the methods to explore the possibility of making quantum circuits, the next ingredient for quantum simulators.