Category Physics

Mr. Zafer Hawash setting up the hanging mercury drop electrode system for conductivity measurement. Credit: Image courtesy of Okinawa Institute of Science and Technology Graduate University – OIST

Researchers have clarified the relationship between air exposure and enhanced electric proprieties in perovskite solar cells. Perovskite solar cells are the rising star in the photovoltaic landscape. Since their invention, <10 years ago, their efficiency has doubled twice and it is now over 22% – an astonishing result in the renewable energy sector. Taking the name ‘perovskite’ from the light-harvesting layer that characterizes them, these solar cells are lighter, cheaper, and more flexible than the traditional crystalline silicon-based cells.

Perovskite solar cells are usually exposed to ambient...

A semi-transparent dye-sensitized solar cell with inkjet-printed photovoltaic portraits of the Aalto researchers (Ghufran Hashmi, Merve Özkan, Janne Halme) and a QR code that links to the original research paper. Credit: Image courtesy of Aalto University

Solar cells have been manufactured already for a long from inexpensive materials with different printing techniques. Especially organic solar cells and dye-sensitized solar cells are suitable for printing. “We wanted to take the idea of printed solar cells even further, and see if their materials could be inkjet-printed as pictures and text like traditional printing inks,” says University Lecturer Janne Halme.

When light is absorbed in an ordinary ink, it generates heat...

Electron and hole wavefunctions: TEM image of a self-assembled quantum dot with a pictorial schematic of the experiment: a quantum dot loaded with a single hole is subject to an in-plane magnetic field (along the x-direction) and optical excitation

A research team from Germany, France and Switzerland has realized qubits in a new form. One day, they might become the information units of quantum computers. To date, researchers have realized qubits in the form of individual electrons. However, this led to interferences and rendered the information carriers difficult to programme and read. The group has solved this problem by utilising electron holes as qubits, rather than electrons.

In order to realize qubits in the form of electrons, an electron is locked in a tiny semiconductor volume, ie q...

The stress-strain curve of the Mg-Sc alloy sheet obtained at -150ºC. The sheet specimen was loaded in tension up to a strain of 3 percent and then unloaded. The alloy sheet shows a superelastic effect. Credit: Yuji Sutou

Mg-Sc alloy shows shape memory properties. This finding raises the potential for development and application of lightweight SMAs across a number of industries, including aerospace. Shape memory alloys (SMAs) show distinctive behaviours such as shape recovery upon heating and have a superelastic effect. They have been used in consumer electronics, housing facilities, personal ornaments, anti-seismic engineering and medical equipment.

Shape memory characteristics were first discovered in an Au-Cd alloy...