A series of copper ridges nearly doubles the resolution of experimental X-ray sensors, enabling more precise identification of the X-ray "fingerprints" of different atoms, researchers at the National Institute of Standards and Technology (NIST) report. The sensors are expected to be powerful tools for astronomy, such as in determining the temperature and motion of matter in space, and for semiconductor materials analysis, helping to differentiate between nanoscale contaminant particles on silicon wafers.
The new design, described in the Nov. 7 issue of Applied Physics Letters,* can measure X-ray energies with an uncertainty of only 2.4 electron volts (eV), breaking through a long-standing 4.5 eV plateau in the performance of superconducting "transition edge" sensors (TES). The cryogenic sensors absorb individual X-rays and measure the energy based on the resulting rise in temperature. The temperature is measured with a bilayer of normal metal (copper) and superconducting metal (molybdenum) that changes resistance in response to the heat from the radiation. The new TES design performs about 40 times better than conventional X-ray sensors made of silicon and lithium.
The primary design change was the addition of five copper ridges patterned on the sensor, perpendicular to the current flow, which blunts or softens the change in resistance from superconducting to normal. NIST holds a patent on the sensor design concept.** The gentler transition reduces unexplained "noise" that degrades measurement precision. A second change was a reduction in device size from 400 to 250 micrometers square, which increases the rise in temperature caused by the X-rays, to better match the broader temperature range of the change in resistance.
Laura Ost | EurekAlert!
Unconventional superconductor may be used to create quantum computers of the future
19.02.2018 | Chalmers University of Technology
Hubble sees Neptune's mysterious shrinking storm
16.02.2018 | NASA/Goddard Space Flight Center
For the first time, a team of researchers at the Max-Planck Institute (MPI) for Polymer Research in Mainz, Germany, has succeeded in making an integrated circuit (IC) from just a monolayer of a semiconducting polymer via a bottom-up, self-assembly approach.
In the self-assembly process, the semiconducting polymer arranges itself into an ordered monolayer in a transistor. The transistors are binary switches used...
Breakthrough provides a new concept of the design of molecular motors, sensors and electricity generators at nanoscale
Researchers from the Institute of Organic Chemistry and Biochemistry of the CAS (IOCB Prague), Institute of Physics of the CAS (IP CAS) and Palacký University...
For photographers and scientists, lenses are lifesavers. They reflect and refract light, making possible the imaging systems that drive discovery through the microscope and preserve history through cameras.
But today's glass-based lenses are bulky and resist miniaturization. Next-generation technologies, such as ultrathin cameras or tiny microscopes, require...
Scientists from the University of Zurich have succeeded for the first time in tracking individual stem cells and their neuronal progeny over months within the intact adult brain. This study sheds light on how new neurons are produced throughout life.
The generation of new nerve cells was once thought to taper off at the end of embryonic development. However, recent research has shown that the adult brain...
Theoretical physicists propose to use negative interference to control heat flow in quantum devices. Study published in Physical Review Letters
Quantum computer parts are sensitive and need to be cooled to very low temperatures. Their tiny size makes them particularly susceptible to a temperature...
15.02.2018 | Event News
13.02.2018 | Event News
12.02.2018 | Event News
19.02.2018 | Materials Sciences
19.02.2018 | Materials Sciences
19.02.2018 | Life Sciences