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Abstract Probabilistic (p-) computing is a physics-based approach to addressing computational problems which are difficult to solve by conventional von Neumann computers. A key requirement for p-computing is the realization of fast, compact, and energy-efficient probabilistic bits. Stochastic magnetic tunnel junctions (MTJs) with low energy barriers, where the relative dwell time in each state is controlled by current, have been proposed as a candidate to implement p-bits. This approach presents challenges due to the need for precise control of a small energy barrier across large numbers of MTJs, and due to the need for an analog control signal. Here we demonstrate an alternative p-bit design based on perpendicular MTJs that uses the voltage-controlled magnetic anisotropy (VCMA) effect to create the random state of a p-bit on demand. The MTJs are stable (i.e. have large energy barriers) in the absence of voltage, and VCMA-induced dynamics are used to generate random numbers in less than 10 ns/bit. We then show a compact method of implementing p-bits by using VC-MTJs without a bias current. As a demonstration of the feasibility of the proposed p-bits and high quality of the generated random numbers, we solve up to 40 bit integer factorization problems using experimental bit-streams generated by VC-MTJs. Our proposal can impact the development of p-computers, both by supporting a fully spintronic implementation of a p-bit, and alternatively, by enabling true random number generation at low cost for ultralow-power and compact p-computers implemented in complementary metal-oxide semiconductor chips.
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This content will become publicly available on December 3, 2025
Yatakemycin biosynthesis requires two deoxyribonucleases for toxin self-resistance
The natural product yatakemycin (YTM) is a potent antimicrobial DNA damaging agent. YtkR4 and YtkR5 are deoxyribonucleases that provide resistance to YTM toxicity by removing the a basic site produced by YtkR2 cleavage of a YTM-adenosine lesion.
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- PAR ID:
- 10563312
- Publisher / Repository:
- Royal Society of Chemistry (United Kingdom)
- Date Published:
- Journal Name:
- RSC Chemical Biology
- ISSN:
- 2633-0679
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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