Scientists generate 'first' stable qubits at room temperature

A team of researchers from Kyushu University's Faculty of Engineering, led by Associate Professor Nobuhiro Yanai, has shattered barriers by achieving quantum coherence at room temperature. Their study reveals the ability to maintain a well defined quantum state, untouched by external disturbances, right here on Earth's surface.

The key to this discovery lies in the marriage of a chromophore—a light absorbing dye molecule—and a metal organic framework (MOF), a nanoporous crystalline material composed of metal ions and organic ligands. "This is the first room temperature quantum coherence of entangled quintets," stated Professor Kobori in a Though the coherence is currently observed in nanoseconds, the findings lay the foundation for future quantum computing and sensing endeavors.

Associate Professor Yanai and collaborators Associate Professor Kiyoshi Miyata and Professor Yasuhiro Kobori embedded the chromophore in the MOF, creating a unique environment for quantum coherence. Quantum coherence is crucial for quantum computing and sensing technologies. But it has remained elusive at room temperature.

The team's innovation involves suppressing molecular motion by introducing a chromophore based on pentacene—a polycyclic aromatic hydrocarbon—into a UiO type MOF. With its densely accumulated chromophores and restrained rotational angle, this MOF structure allowed the researchers to achieve a room temperature quantum coherence that has never been witnessed before.

Exciting electrons to reveal quantum coherence Electrons were excited with microwave pulses to delve into the science behind it, revealing a quantum coherence of the state lasting over 100 nanoseconds. While this may seem like a fleeting moment, it's a huge stride toward designing materials capable of generating multiple qubits at room temperature.

Associate Professor Yanai envisions a future where quintet multiexciton state qubits can be efficiently generated by searching for guest molecules inducing suppressed motions and developing suitable MOF structures. This opens the exciting prospect of room temperature molecular quantum computing based on multiple quantum gate control and quantum sensing of various target compounds.

Quantum computing, touted as the next major technological advancement, is one step closer to reality thanks to this research. Quantum sensing, leveraging the quantum properties of qubits, promises higher resolution and sensitivity in sensing technology, marking a paradigm shift from traditional techniques.

As we stand on the cusp of a quantum revolution, the room temperature quantum coherence of quintet states could be the key to unlocking the full potential of quantum technologies that were once deemed only possible at extreme temperatures. Their study was published in on January 3 and can be found ..