(GIST OF SCIENCE REPORTER) Can Graphene Valleytronics Pave the Way to Household Quantum Computers?

[December-2021]

Quantum Computers such as those at Google, IBM, or Microsoft — are large, complex, and expensive, and can only operate computers that often make the news —at ultra-low temperatures of nearly –200°C. This makes them very impractical for use on a large scale.
Researchers from the Indian Institute of Technology (IIT) Bombay have found a way to use pristine graphene for encoding, processing, and storing quantum information, opening doors to much simpler, small-sized quantum computers that can operate at room temperature.
Quantum computers have recently become a hot-button topic because of their theoretical potential to outperform conventional computers by several orders of magnitude in terms of speed.

Quantum Computing will enable the faster execution of molecular simulations, big data analysis, deep learning, and other computationally intensive tasks, in turn, accelerating molecular research and the development of new drugs, helping in the search for cures to complex diseases, including COVID-19, not to mention the ways in which it can create uncrackable cybersecurity measures and revolutionise artificial intelligence.
A quantum computer can achieve these feats because it encodes information in quantum bits rather than the binary “0” or “1” that regular electronics use. Quantum bits are superpositions of “0” and “1”, and can therefore take intermediate values, making computations much faster.

Such quantum computation is not yet possible at room temperature; and existing computers, such as those owned by Google, IBM, and Microsoft, have to be kept at ultra-low temperatures below –196.1°C, which makes them costly and impractical to operate.
A very promising novel approach for encoding quantum information is actively being explored to overcome these challenges: valleytronics.
Aside from their charge, electrons have another parameter that can be manipulated: their “valley pseudospin,” which are the local minima in the energy bands of solids that can be occupied by electrons. By manipulating how many electrons occupies each of the valleys, quantum information can be encoded, processed, and stored at less restrictive temperatures.