Lifeboat Foundation

A new device converts a stream of microwave photons into an electric current with high efficiency, which will benefit quantum information technologies.

Technologies for quantum computing, sensing, and communication process information stored in quantum bits (qubits) by using microwave photons. But detecting such photons accurately and at high rates—to read out the changing states of a quantum computer, for example—is a challenge, since they have much less energy than visible or infrared photons. Now researchers have demonstrated a detection method based on the fact that a photon can assist in the quantum tunneling of an electron through a superconducting junction [1]. The technique converts a stream of microwave photons into a flow of electrons far more effectively than other methods, showing an efficiency of 83%, and it will be of immediate use in quantum technologies.

Building good detectors of microwave photons is inherently difficult, says Julien Basset of the University of Paris-Saclay, because such photons lack the energy needed to excite electrons in semiconductors into the conduction band, thereby generating a current that can be measured. Researchers have been pursuing several techniques, but none works well for a continuous stream of photons, in which multiple photons may arrive simultaneously. For such continuous operation, as would likely be required in many practical quantum information devices, the best efficiency demonstrated so far has been only a few percent, Basset says.

An analysis of the brightest gamma-ray burst ever observed reveals no difference in the propagation speed of different frequencies of light—placing some of the tightest constraints on certain violations of general relativity.

A magnet-and-coil system reveals how acoustic waves reflect and refract when the host medium suddenly changes elasticity.

A soft x-ray magnetic imaging technique makes possible the study of a wide range of magnetic materials.

Although natural-killer-cell therapies are safer than T-cell therapies and offer other advantages, they require upgrades to overcome their limited lifespan and susceptibility to immunosuppression.

ABOVE: Researchers recapitulate electrical gradients in vitro to help guide stem cell differentiation for neural regeneration. ©istock, Cappan.

The dance of development is electric. Bioelectrical gradients choreograph embryonic growth, signaling to stem cells what cell types they should become, where they should travel, who their neighbors should be, and what structures they should form.¹ The intensity and location of these signals serve as an electrical scaffold to map out anatomical features and guide development. Bioelectricity also shapes tissue regeneration.² Tapping into these mechanisms is of special interest to researchers who grapple with the challenge of regenerating injured nerves.³

One such curious team from Stanford University and the University of Arizona recently reported a new approach using electrically conductive hydrogels to induce differentiation of human mesenchymal stem cells into neurons and oligodendrocytes in vitro.⁴ Their findings, published in the Journal of Materials Chemistry B, provide important proof of principle for future studies of biocompatible materials to electrically augment transplanted and endogenous cells after injury.

HAPPI seeks demonstrations of low-loss, high-density optical interconnects using scalable manufacturing compatible with microelectronics.

Related: SDR: a spectrum of possibilities

NAVWAR awarded the order on behalf of the Navy’s Program Executive Office for Command, Control, Communication, Computers, and Intelligence (PEO C4I) in San Diego.

The AN/USC-61© is a maritime software-defined radio (SDR) that has become standard for the U.S. military. The compact, multi-channel DMR provides several different waveforms and multi-level information security for voice and data communications.

Organoids of mammary glands can help researchers more efficiently study lactation, with findings that could apply to fields ranging from agriculture to medicine.