Lifeboat Foundation

The next generation of computing and information processing lies in the intriguing world of quantum mechanics. Quantum computers are expected to be capable of solving large, extremely complex problems that are beyond the capacity of today’s most powerful supercomputers.

New research tools are needed to advance the field and fully develop quantum computers. Now Northwestern University researchers have developed and tested a theoretical tool for analyzing large superconducting circuits. These circuits use superconducting quantum bits, or qubits, the smallest units of a quantum computer, to store information.

Circuit size is important since protection from detrimental noise tends to come at the cost of increased circuit complexity. Currently there are few tools that tackle the modeling of large circuits, making the Northwestern method an important contribution to the research community.

Circa 2004

To what extent do photosynthetic organisms use quantum mechanics to optimize the capture and distribution of light? Answers are emerging from the examination of energy transfer at the submolecular scale.

The first law of photosynthetic economics is: “A photon saved is a photon earned.” Research into the factors behind this principle has been burgeoning, and has recently culminated in a paper in Physical Review Letters by Jang et al.¹ in which the authors look at photosynthetic energy transfer at the quantum level.

Researchers describe how electrons move through two-dimensional layered graphene 0 findings that could lead to advances in the design of future quantum computing platforms.

New research published in Physical Review Letters describes how electrons move through two different configurations of bilayer graphene, the atomically-thin form of carbon. This study, the result of a collaboration between Brookhaven National Laboratory, the University of Pennsylvania, the University of New Hampshire, Stony Brook University, and Columbia University 0 provides insights that researchers could use to design more powerful and secure quantum computing platforms in the future.

“Today’s computer chips are based on our knowledge of how electrons move in semiconductors, specifically silicon,” says first and co-corresponding author Zhongwei Dai, a postdoc at Brookhaven. “But the physical properties of silicon are reaching a physical limit in terms of how small transistors can be made and how many can fit on a chip. If we can understand how electrons move at the small scale of a few nanometers in the reduced dimensions of 2-D materials, we may be able to unlock another way to utilize electrons for quantum information science.”

Cumrun Vafa is a theoretical physicist at Harvard. Please support this podcast by checking out our sponsors:
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CORRECTIONS:
- I’m currently hiring folks to help me with editing and image overlays so there may be some errors in overlays (as in this episode) as we build up a team. I ask for your patience.
- At 1 hour 27 minute mark, we overlay an image of Brian Greene. We meant to overlay an image of Michael Green, an early pioneer of string theory: https://bit.ly/michael-green-physicist.
- The image overlay of the heliocentric model is incorrect.

Continue reading “Cumrun Vafa: String Theory | Lex Fridman Podcast #204” »

Cold clouds of atoms—Bose-Einstein Condensates—will test quantum gravity, enable atom-scale lithography and prospect for minerals from afar.

New tools are required if businesses are to take advantage of quantum computing, argues Horizon’s Joe Fitzsimons.

Circa 2019

LONDON — A laboratory in Switzerland has found a way of using a laser to change and regulate the polarization, wavelength and intensity of light in “excitons” in 2D materials, creating the potential for a new generation of transistors with less energy loss and heat dissipation, opening up the potential for low-power quantum computing.

Excitons are created when an electron absorbs light and moves into a higher energy level, or “energy band” as it is called in solid quantum physics. This excited electron leaves behind an “electron hole” in its previous energy band. And because the electron has a negative charge and the hole a positive charge, the two are bound together by an electrostatic force called a Coulomb force. It’s this electron-electron hole pair that is referred to as an exciton.

Continue reading “‘Excitons’ Show Potential for Low-Power Quantum Computing” »

Circa 2012

Quantum ground-state problems are computationally hard problems for general many-body Hamiltonians; there is no classical or quantum algorithm known to be able to solve them efficiently. Nevertheless, if a trial wavefunction approximating the ground state is available, as often happens for many problems in physics and chemistry, a quantum computer could employ this trial wavefunction to project the ground state by means of the phase estimation algorithm (PEA). We performed an experimental realization of this idea by implementing a variational-wavefunction approach to solve the ground-state problem of the Heisenberg spin model with an NMR quantum simulator. Our iterative phase estimation procedure yields a high accuracy for the eigenenergies (to the 10–5 decimal digit).

Isaac Newton’s groundbreaking scientific productivity while isolated from the spread of bubonic plague is legendary. University of California San Diego physicists can now claim a stake in the annals of pandemic-driven science.

A team of UC San Diego researchers and colleagues at Purdue University have now simulated the foundation of new types of artificial intelligence computing devices that mimic brain functions, an achievement that resulted from the COVID-19 pandemic lockdown. By combining new supercomputing materials with specialized oxides, the researchers successfully demonstrated the backbone of networks of circuits and devices that mirror the connectivity of neurons and synapses in biologically based neural networks.

The simulations are described in the Proceedings of the National Academy of Sciences (PNAS).