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New practice tool for quantum computer coding: OpenFermion

In a global effort, quantum computers are rapidly being developed. In the meantime, researchers have to learn how to write code for these devices, which are fundamentally different from conventional computers. A collaboration of scientists led by Google, and including physicists from Leiden and Delft, have developed a practice tool for chemists: OpenFermion.

Companies and universities across the globe are working hard on developing a quantum computer. Instead of a collection of conventional bits, which can take on two values, a quantum computer is a collection of linked qubits, which entangle to process a much larger set of information. For each extra qubit added to the quantum computer, its power compared to a regular computer doubles. This exponential increase makes even a relatively small quantum computer able to solve problems that are impossible for conventional computers. This goes only for specific problems, such as decryption, modelling molecules for medicine, or designing new catalysts for cleaner fuel burning.


To actually make use of quantum computers, we also need software. And while most scientists know how to write code for ordinary computers, they are completely new to the quantum coding scene. To let the community ease into this new discipline, tools such as Project Q, quantumsim, qHiPSTER, QISKIT, Q#, and Liquid have already been developed for scientists to practice coding on simulated quantum computers and small real devices.


A collaboration of scientists led by Google, and including PhD students Tom O’Brien and Mark Steudtner from the groups of Carlo Beenakker and Stephanie Wehner, have now launched a software tool specifically for chemistry research: OpenFermion. On the one hand, it supports chemists towards writing quantum code to simulate complicated chemistry, for example new medicine or catalyst molecules. On the other hand, it allows coding experts to work on a chemical problem even though they have no background in that field.

In an accompanying paper, the collaboration provides examples of quantum code and elaborates on their open source philosophy.