The study of photonics has yielded some of the most advanced technologies in the world today; it is a rapidly growing field of research and development, with applications in high-tech industry. The applications of photonics as an ‘enabling’ technology are very broad. They include;

  • Medical imaging
  • Flat screen display and charge-coupled device video cameras
  • Biometric security, image processing
  • Energy technology (e.g. photovoltaics)
  • Optical communications technology (e.g. fibre optics, lasers and infrared (IR) links)
  • Astronomy and next-generation and displays.
  • Defence technologies (e.g. spy and weather satellites, night vision, holography thermal cameras)
  • and much more

Thermal imaging

Photonics is the control, detection and the generation of photons (light) with electronic signals, and vice versa. The devices such as sensors, detectors, mobile phones, web communication —that we use in our daily life— are based on conversion of photo/electro signal into electro/photo signal. The physical mechanism in the conversion process is the light-matter interaction. Hence, the absorbing (detecting) system (quantum in nature) is chosen by considering the part of the electromagnetic spectrum at which the observation is carried out. In optic detectors band gap of semiconductors (~2 eV) are used, while one adopts the low-energetic defect state transitions (10s of meV) in an infrared detector. Radio signals with much longer wavelengths are converted using metal antennas of compatible sizes.

All of these devises use a large number of photons in the conversion processes. Therefore, light-matter interaction in such apparatus can be described as a simple (single) field. The recent progresses In the control and management of light and nano/micro devices enabled us to perform operations with a single photon, single electron or a single phonon.

Such small devices, working in the quantum regime, necessitates an intense understanding on quantum optics. In this regime, a photon must be described in the second quantized regime; where a light pulse must be considered as the superposition of the states including different number of photons, e.g. |Ψ˃=a0|0> + a1|1> + a2|2> ….. In this regime, interesting physics such as quantum entanglement, superposition, squeezing emerges. For example, the motion of an AFM tip can be cooled in an optical cavity by interactions with the cavity mode. The oscillations on the tip can be brought down approximately to a single phonon occupation while the sample is kept at room temperature; in which without cooling occupation is ~107 phonons. In addition to cooling the tip can be squeezed via light, whose x-position can be measured within ultimate precision.

In our institute, we conduct research on quantum optical features of optoelectronics and optomechanics, as well as obtaining progression on the conventional optoelectronic devises.

Hacettepe Üniversitesi Nükleer Bilimler Enstitüsü
06800 Beytepe / Ankara
Tel: (0312) 297 68 80