Modulation and frequency response of GDDs in the millimeter wave/THz region

Alasgarzade, N.
Takan, T.
Uzun Kaymak, İlker Ümit
Altan, Hakan
New methods are being developed for efficient detection of terahertz waves. While many detection techniques show promise their commercial development is still limited due to the overall complexity and cost of the imaging system. Using commercially available neon indicator lamps the interaction mechanism between the glow plasma and the millimeter / THz wave is investigated in detail as a function of the device speed, sensitivity to frequency and polarization of the light. A lock-in amplifier was used to measure the response up to 90kHz when the GDD was placed at the focus of a 113GHz center frequency reconfigured Dielectric Resonating Oscillator (DRO) driven multiplied Schottky diode source. In addition the polarization sensitivity of the GDD was tested for two different scenarios whereby rotating the GDD the detected signal is observed to agree well with Malus's Law for one particular orientation. Furthermore, the frequency dependent GDD-THz interactions are investigated using a 240-380 GHz tunable continuous wave radiation source. Employing both systems allow us to understand the response of GDDs with respect to modulation frequency, RF frequency and polarization orientation. Resonance effects, frequency sensitivity and geometrical structures of GDDs are studied for the purpose of obtaining better performance in THz-GDD interaction for applications including general THz wave detection and imaging.


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Understanding the Effect of THz/mm wave - Plasma Interaction on the Brightness of Glow Discharge Detectors
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Today, the fact that non-ionizing THz and mm wave can be used in many areas reveals the necessity of devices that can efficiently detect these waves. Compared to existing commercial detectors, cost-effective neon indicator lamps acting as glow discharge detectors (GDDs) are known to be better in speed and responsivity. In GDDs, detection occurs as a result of the interaction between radiation and plasma. Although there are many studies in the literature trying to explain this interaction, these studies are ...
Citation Formats
N. Alasgarzade, T. Takan, İ. Ü. Uzun Kaymak, A. B. ŞAHİN, and H. Altan, “Modulation and frequency response of GDDs in the millimeter wave/THz region,” 2015, vol. 9651, Accessed: 00, 2020. [Online]. Available: