SRON develops new technologies to detect radiation from space, including
X-rays,
infrared radiation and
optical light. For X-ray missions such as
Athena, SRON scientists develop
Transition Edge Sensors (TES). These work at the exact temperature at which their material is on the verge of a
superconducting state. When an X-ray photon falls in from space, the material heats up a tiny bit and the superconducting state collapses. The readout current drops as a result, and the instrument knows that it has detected a photon. The energy of the photon is proportional to how much superconductivity is lost. For infrared and exoplanet missions,
Kinetic Inductance Detectors (KID) are developed at SRON. These also work at superconducting temperatures.
Kinetic inductance is the manifestation of inertia in mobile charge carriers. In an alternating current the direction of a current keeps changing, which takes effort, just like it costs some effort to shake a mass back and forth. In a superconducting state this effort doesn't apply because electrons have formed pairs and therefore flow without any resistance through the material. When a photon hits from space, it breaks up several electron pairs, hampering the superconducting state and the kinetic inductance increases. This is measured by the instrument and it knows that it has detected a photon. The energy of the photon is proportional to the amount of electron pairs are broken up. Other infrared missions such as
GUSTO make use of
Hot Electron Bolometer (HEB) technology. ==National and international partners==