Scientists Have Built a Functional 'Hybrid' Logic Gate for Use in Quantum Computers

Oxford’s Quantum Leap

In a potential quantum computer breakthrough, scientists have shown that entangling atoms from different elements can address the problems of quantum memory errors while functioning within a logic gate framework. Notably, the atoms are also able to pass the test for true entanglement.

This research is double notable, as two research teams have independently demonstrated this capability.

Oxford’s Networked Quantum Information Technologies (NQIT) Hub is focused on developing quantum technologies with processing power capable of overshadowing any supercomputers found today, and they just came one step closer to doing just that.

Oxford researchers published a new paper in the journal Nature that demonstrates the work progression in the Hub.

In the paper, co-author Professor David Lucas explains that “the development of a ‘quantum computer’ is one of the outstanding technological challenges of the 21st century. A quantum computer is a machine that processes information according to the rules of quantum physics, which govern the behaviour of microscopic particles at the scale of atoms and smaller.”

Professor Lucas explains that quantum computing is a fundamentally different way of processing information, saying, “It turns out that this quantum-mechanical way of manipulating information gives quantum computers the ability to solve certain problems far more efficiently than any conceivable conventional computer. One such problem is related to breaking secure codes, while another is searching large data sets. Quantum computers are naturally well-suited to simulating other quantum systems, which may help, for example, our understanding of complex molecules relevant to chemistry and biology.”

Learn more about these technologies, and the role of quantum technology, in the video that it posted below.

 

Quantum Logic Gate

The NQIT project’s principal goal is developing the constituent elements of a quantum computer based on trapped atomic ions, one of the leading technologies for building a quantum computer.

“Each trapped ion (a single atom, with one electron removed) is used to represent one ‘quantum bit’ of information. The quantum states of the ions are controlled with laser pulses of precise frequency and duration. Two different species of ion are needed in the computer: one to store information (a "memory qubit") and one to link different parts of the computer together via photons (an "interface qubit"),” explains Professor Lucas.

The paper demonstrates the all-important “logic gate” between the differing species of ion, particularly between the common isotope calcium-40 and the rare isotope calcium-43.

“The logic gate, which was first demonstrated for same-species ions at NIST Boulder (USA) in 2003, allows quantum information to be transferred from one qubit to another; in the present work, the qubits reside in the two different isotopes, stored in the same ion trap,” says Professor Lucas.