Advancing Quantum Computing in the U.S.

Researchers at the Department of Energy’s Oak Ridge National Laboratory have achieved a significant milestone in quantum computing by simulating a key quantum state at one of the largest scales reported, with support from the Quantum Computing User Programme (QCUP). This achievement has the potential to advance quantum simulation capabilities for the next generation of quantum computers, opening up new possibilities for solving complex problems in areas such as materials science, chemistry, and cryptography.

The study collaborated with a quantum computing company and utilised the H1-1 computer to model a quantum version of a classical mathematical model that tracks how diseases spread. By using quantum bits or qubits, the researchers simulated the transition between active states, such as infection, and inactive states, such as recovery or death. This quantum approach is particularly relevant for modelling transitional states that are challenging to calculate on conventional computers.

Classical computers store information in bits that can be either 0 or 1. In contrast, quantum computing leverages the principles of quantum mechanics to store information in qubits, which can exist in multiple states simultaneously through quantum superposition. This allows qubits to carry more information than classical bits and enables them to study complex questions like transitional states more effectively.

The researchers utilised the Quantum Computing User Programme, which awards time to privately owned quantum processors around the country to support research projects. By obtaining time on the quantum computing company’s computer, which uses trapped ions as qubits, the researchers were able to simulate a system where active qubits can activate neighbouring qubits or become inactive. They employed a technique known as qubit recycling to eliminate degraded qubits and avoid errors in their calculations.

The team’s approach showed promising results, indicating that with 20 qubits, they could simulate a quantum system nearly four times the size. They estimate that with 70 qubits, their approach could equal or surpass a classical computer’s capabilities in simulating complex quantum systems.

This research represents a significant step forward in quantum computing, demonstrating the potential for quantum computers to outperform classical machines in speed and power. The next steps include applying qubit recycling to simulate the properties of materials and calculate their lowest energy states, known as quantum ground states. These advancements have the potential to revolutionise various fields, including materials science, chemistry, and cryptography, by providing more accurate and efficient simulations.

Quantum computing has the potential to revolutionise various fields by providing more accurate and efficient simulations. In materials science, for example, quantum computers could help researchers design new materials with specific properties, leading to advancements in electronics, energy storage, and more.

In chemistry, quantum computers could enable researchers to simulate chemical reactions with unprecedented accuracy, leading to the development of new drugs and materials. In cryptography, quantum computers could break current encryption schemes but also enable the development of new, quantum-resistant encryption methods.

The researchers envision that their work will pave the way for further advancements in quantum computing and help unlock the full potential of this revolutionary technology. By pushing the boundaries of what is possible in quantum simulation, they aim to contribute to a future where quantum computers are widely used to tackle some of the most challenging problems facing science and society.

In the future, quantum computers might be used to simulate complex quantum systems with unprecedented accuracy, leading to discoveries in fundamental physics. Quantum computers could also revolutionise cryptography, enabling the creation of unbreakable encryption schemes based on quantum principles.