Spatial modulation of THz beams for imaging applications

Date

2015-10-16

Author

Altan, Hakan

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Techniques based on compressive sensing allow us to image fields at faster rates and at our labs in METU we have been experimenting with imaging based on spatial modulation of THz beams using single pixel detectors [1]. However these studies are based on discrete patterns using metal sheets. These techniques would benefit greatly if we could modulate the THz field. For example, optical modulators play a key role in optoelectronics and communication systems. Electro-optic, acousto-optic and thermo-optic effects are well established mechanisms to control intensity, phase or polarization of light in the visible and near infrared frequencies. Efficient control of terahertz waves, however, has been a challenge due to the lack of a THz active material. Graphene is a viable material for active terahertz (THz) devices [2]. Electrostatic tuning of high mobility carriers on graphene provides an electrical means for controlling THz waves. Here we demonstrate a terahertz intensity modulator using a graphene supercapacitor which consists of two large area graphene electrodes and electrolyte medium. By patterning the device into an array the potential for rapid imaging is demonstrated. These works are discussed in the context of current mm wave/THz stand-off imaging investigations taking place in our laboratories.

URI

https://hdl.handle.net/11511/87271
http://ww2.comsats.edu.pk/LightAndLife2015/files/AbstractsBook.pdf

Conference Name

International Symposium on Light and Life, 14-16 October 2015

Collections

Department of Physics, Conference / Seminar

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Citation Formats

H. Altan, “Spatial modulation of THz beams for imaging applications,” presented at the International Symposium on Light and Life, 14-16 October 2015, Islamabad, Pakistan, 2015, Accessed: 00, 2021. [Online]. Available: https://hdl.handle.net/11511/87271.