A MEMS version of a legacy delay-line memory has been demonstrated as a viable scratchpad memory for future quantum computers by the National Institute of Standards and Technology (NIST, Boulder, Colorado).
The memory element in the MEMS (microelectromechanical system) resonates when hit with microwave pulses whose amplitude and phase encode the quantum information. Because the mechanical oscillations continue during the coherence time of a typical quantum operation, NIST believes the micron-sized memory could store temporary values during quantum calculations.
In principle, the MEMS memory performs like a legacy delay-line memory from early computer days, which stored scratchpad values in acoustic waves traveling down a column of mercury. In recent years, the same delay-line concept has been used in optical systems that measure out lengths of fiber cable to temporarily store information.
MEMS micro-drum and circuit on a sapphire backing. JILA researchers demonstrated that the drum might be used as a memory device in future quantum computers.
Image source: NIST
The current prototype has demonstrated 65 percent efficiency in temporarily storing quantum information, but NIST believes it can improve the data exchange between microwave photons, which excite the device, and the mechanical phonons, from which stored values are read out, making it a viable scratchpad memory for future quantum computers.
David Patterson, known for his pioneering research that led to RAID, clusters and more, is part of a team at UC Berkeley that recently made its RISC-V processor architecture an open source hardware offering. We talk with Patterson and one of his colleagues behind the effort about the opportunities they see, what new kinds of designs they hope to enable and what it means for today’s commercial processor giants such as Intel, ARM and Imagination Technologies.