The first-ever spectrometer made from quantum dots has been unveiled by Jie Bao of Tsinghua University in China and Moungi Bawendi of the Massachusetts Institute of Technology in the US. According to its inventors, the instrument could be produced commercially to be as small, inexpensive and simple as a mobile-phone camera. Such compact spectrometers could find a wide range of applications, from gathering scientific data on space missions to sensors integrated within household appliances.


Demming qd


Spectrometry measures the intensity of light as a function of wavelength and is used to study various properties of light-emitting and light-absorbing substances. This makes it an invaluable analytical technique that is used in a broad range of scientific and technological disciplines. Most spectroscopic techniques involve dispersing light in terms of its wavelength. A prism, for example, can be used to bend light into its constituent wavelengths (colours) and a spectrum can then be acquired using a position-sensitive light detector. Bao and Bawendi have taken a different approach, using quantum dots to create an array of band-pass filters for the light to pass through before it reaches a position-sensitive detector.