NTT, the University of Tokyo, RIKEN, and the Japan Science and Technology Agency announced that they had succeeded in real-time quantum signal measurement at 43 GHz. It is expected to realize super quantum computers, improve the performance of existing computers, and reduce power consumption.
In a measurement-induced optical quantum computer using “time domain multiplexing technology” that can achieve large scale and high speed, photons arrive at high speed instead of the “standing wave qubit” that is commonly used in superconducting qubits. The feature is that it uses a traveling wave cooking bit. By arranging this on the time axis, it is said that there is no need to increase the size of the device or integrate the elements when the scale is increased.
The three parties have developed a method for applying optical communication, which has been difficult until now, by amplifying light while retaining photon information using an “optical parametric amplifier.” Conventionally, when a detector for optical communication is applied as it is to the field of photon quantization, although a sufficient band can be secured, there is a problem that the quantum information deteriorates and is difficult to use. On the other hand, although detectors designed for conventional light quanta do not degrade quantum information, the operating clock is only a few MHz, making high-speed calculation difficult. This time, the three parties succeeded in realizing high-speed calculation and retention of quantum information by using an “optical parametric amplifier” using a PPLN waveguide.
According to Asuka Inoue, a researcher at NTT Advanced Integrated Device Laboratories, as a result of experiments using a 43 GHz detector for optical communication and a real-time oscilloscope, the quantum noise compression rate is about 65%, which is the minimum required for optical quantum computing operation. Since it exceeds the quantum noise compression value of 60%, it is expected to be able to realize quantum operations that operate at more than 1000 times the number of clocks compared to conventional technology.
Left: Professor Yoshizawa, Graduate School of the University of Tokyo.Right = Researcher Inoue, NTT Device Technology Laboratories
Combining optical communication and photon technologies will enable high-speed quantum computation in a band of over 100 GHz, and by using long-division multiplexing technology, it will be possible to create a multi-core quantum processor without increasing the scale of the device. Because it is possible, it is said that a super quantum computer with 100 multi-cores in the 100 GHz band, which surpasses conventional computers, can be realized.
Currently, about 30% of the world’s energy consumption is due to computers. Professor Akira Yoshizawa of the Graduate School of Engineering, the University of Tokyo, expressed his hopes that the newly developed technology will contribute to power saving, and that it will also contribute to environmental issues. As for the time of practical application, it is said that it will be released to the cloud in a state that can be used for limited problems in about a year and a half.