Journal
SENSORS
Volume 11, Issue 6, Pages 6003-6014Publisher
MDPI
DOI: 10.3390/s110606003
Keywords
terahertz; optical microsensor; quantum-cascade laser; active resonator
Funding
- Austrian Scientific Fund FWF (SFB ADLIS, SFB IR-ON, DK CoQuS)
- Austrian nano initiative project (PLATON)
- Austrian Society for Microelectronics (GMe)
- Austrian Science Fund (FWF) [W1210] Funding Source: Austrian Science Fund (FWF)
- Austrian Science Fund (FWF) [F 2503] Funding Source: researchfish
Ask authors/readers for more resources
The terahertz (THz) spectral region, covering frequencies from 1 to 10 THz, is highly interesting for chemical sensing. The energy of rotational and vibrational transitions of molecules lies within this frequency range. Therefore, chemical fingerprints can be derived, allowing for a simple detection scheme. Here, we present an optical sensor based on active photonic crystals (PhCs), i.e., the pillars are fabricated directly from an active THz quantum-cascade laser medium. The individual pillars are pumped electrically leading to laser emission at cryogenic temperatures. There is no need to couple light into the resonant structure because the PhC itself is used as the light source. An injected gas changes the resonance condition of the PhC and thereby the laser emission frequency. We achieve an experimental frequency shift of 10(-3) times the center lasing frequency. The minimum detectable refractive index change is 1.6 x 10(-5) RIU.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available