A research team led by Professor Chih-Sung Chuu from the Department of Physics and the Center for Quantum Technology at National Tsing Hua University (NTHU) in Taiwan has achieved a groundbreaking milestone in quantum computing.
The team has successfully developed the world’s smallest quantum computer, which operates using just one photon. This marks the first time an optical quantum computer has been created in Taiwan, showcasing the country’s growing prowess in quantum technology.
The team demonstrated their innovation at a press conference, showcasing how their optical quantum computer, running within an optical fiber loop with a single photon, can perform complex mathematical operations. These include prime factorizations such as 15 = 5 x 3, a task that highlights the computer’s ability to execute quantum algorithms.
This achievement represents the first time a single high-dimensional photon has been used to perform such operations. The team’s research was published in the September issue of Physical Review Applied.
A Quantum Leap in Computing
NTHU President W. John Kao praised the team’s work as a significant milestone in quantum computing. Reflecting on his visit to a leading quantum computer laboratory in the United States, Kao noted the massive cooling systems required to maintain temperatures as low as -273°C.
In contrast, the optical quantum computer developed at NTHU operates at room temperature and is compact enough to fit into a small box. “I hope that one day we will all have an optical quantum computer on our desk!” Kao exclaimed.
Professor Chuu explained that photons, the elementary particles of light, are the foundation of this innovation. To maximize the information-carrying capacity of a single photon, the team developed a technology that encodes information into 32 dimensions within one photon.
To put this into perspective, a one-dimensional object is a line, a two-dimensional object has length and width, and a three-dimensional object includes height. The NTHU team’s quantum computer, however, encodes information in 32 dimensions (or time bins), setting a new world record.
Chuu likened this advancement to transforming a single-seat bicycle into a 32-seat bicycle, dramatically increasing its capacity. Traditional optical quantum computers rely on multiple photons, which are generated probabilistically and often appear and disappear unpredictably, making it challenging to synchronize them.
By focusing on a single photon, the team has overcome this limitation. Their next goal is to further increase the information capacity of a single photon to enable even more complex quantum operations.
How Quantum Computers Work
Unlike conventional computers, which use electricity to transmit data across circuit boards, optical quantum computers use light to transmit data and leverage the principles of quantum mechanics to perform operations.
While traditional computers rely on binary digits (bits) that represent either 0 or 1, quantum computers use quantum bits (qubits), which can exist in a state of superposition—simultaneously representing both 0 and 1. This unique property allows quantum computers to perform complex calculations, such as prime factorizations and big data searches, hundreds of millions of times faster than traditional computers.
Future Applications and Impact
Chung-Yu Mou, Dean of the College of Science at NTHU, highlighted that this optical quantum computer is the result of independent research and development supported by the university’s Center for Quantum Technology. The achievement underscores NTHU’s technical expertise and commitment to innovation in quantum technology.
The potential applications of optical quantum computers are vast, ranging from drug discovery and logistics optimization to information security. Additionally, their unparalleled efficiency is expected to revolutionize fields such as artificial intelligence, where they could far surpass the capabilities of current supercomputers.
A New Era of Quantum Computing
The development of the world’s smallest quantum computer using just one photon is a testament to the ingenuity and dedication of the NTHU research team.
By pushing the boundaries of quantum technology, they have opened the door to a future where quantum computers could become as commonplace as traditional desktops, transforming industries and solving problems that were once thought to be insurmountable. This breakthrough not only positions Taiwan as a leader in quantum research but also brings us one step closer to a new era of computing.
