A magentic molecule that acts as a quantum logic gate

The molecules developed in the study were discovered by the Magnetism and Functional Molecules Group (GMMF) at the UB’s Faculty of Chemistry
The molecules developed in the study were discovered by the Magnetism and Functional Molecules Group (GMMF) at the UB’s Faculty of Chemistry
Research
(19/09/2011)

A recent study carried out by a cross-disciplinary team of researchers from the UBʼs Department of Inorganic Chemistry, the Institute of Materials Science of Aragon (ICMA) and the Institute of Nanoscience of Aragon (INA), indicates that certain magnetic molecules could be used as basic components of future quantum computers. The study, published in the latest issue of the journal Physical Review Letters, shows that a molecule containing two magnetic atoms can exhibit the behaviour of a universal controlled-NOT (CNOT) quantum gate.

The molecules developed in the study were discovered by the Magnetism and Functional Molecules Group (GMMF) at the UB’s Faculty of Chemistry
The molecules developed in the study were discovered by the Magnetism and Functional Molecules Group (GMMF) at the UB’s Faculty of Chemistry
Research
19/09/2011

A recent study carried out by a cross-disciplinary team of researchers from the UBʼs Department of Inorganic Chemistry, the Institute of Materials Science of Aragon (ICMA) and the Institute of Nanoscience of Aragon (INA), indicates that certain magnetic molecules could be used as basic components of future quantum computers. The study, published in the latest issue of the journal Physical Review Letters, shows that a molecule containing two magnetic atoms can exhibit the behaviour of a universal controlled-NOT (CNOT) quantum gate.

Quantum computers use the laws of quantum physics as the basis for carrying out logical operations. Experts believe that this technology is set to revolutionize the world of computing thanks to its capacity to complete tasks that are beyond the scope of current (“classical”) computers, such as the simulation of new materials, searches in large databases or the secure encryption of confidential information. Scientists have spent years trying to find the right materials for basic memory units (qubits) and logic gates suitable for the construction of quantum computers.

The molecules developed in the study were discovered by the Magnetism and Functional Molecules Group (GMMF), which is led by the lecturer Guillem Aromí of the Department of Inorganic Chemistry. These types of species contain two magnetic terbium atoms, and one of the principal outcomes of the research is the design of a molecular structure that distinguishes between these two atoms, when nature tends to produce symmetrical molecules. Despite the identical structure of the terbium atoms, in the molecule identified in the study they are encapsulated in different organic corpuscles. The experiments conducted at the ICMA have demonstrated that each one exhibits different magnetic properties and that the spin of one atom (the target qubit) carries out a logic operation according to the state of the other (the control qubit), therefore meeting the criteria of a CNOT gate.

One of the advantages of this new material is that its production requires relatively simple chemical methods. As such, it is a much cheaper and more efficient solution than other alternatives, since enormous quantities of identical molecules can be produced in a single reaction. The study is a significant step towards the development of quantum computing architectures that can be integrated into larger chips, making them ideal for more complex tasks.

 

Original article:

 

Luis, F.; Repollés, A.; Martínez-Pérez, M. J.; Aguilà, D.; Roubeau, O.; Zueco, D.;  Alonso, P. J.; Evangelisti, M.; Camón, A.; Sesé, J.; Barrios, L. A. and Aromí, G. “Molecular Prototypes for Spin-Based CNOT Quantum Gates”. Physical Review Letters. DOI: 10.1103/PhysRevLett.107.117203