Electrically controlled terahertz spatial light modulators with graphene arrays

Kakenov, Nurbek
Takan, Taylan
Özkan, Vedat Ali
Balci, Osman
Polat, Emre O.
Altan, Hakan
Gate-tunable high-mobility electrons on atomically thin graphene layers provide a unique opportunity to control electromagnetic waves in a very broad spectrum. In this paper, we describe an electrically-controlled multipixel terahertz light modulators. The spatial light modulator is fabricated using two large-area graphene layers grown by chemical vapor deposition and transferred on THz transparent and flexible substrates. Room temperature ionic liquid, inserted between the graphene, provides mutual gating between the graphene layers. We used passive matrix addressing to control local charge density thus the THz transmittance. With this device configuration, we were able to obtain 5x5 arrays of graphene modulator with 65% modulation between 0.1 to 1.5 THz.
IEEE MTT-S International Microwave Symposium (IMS)


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Citation Formats
N. Kakenov et al., “Electrically controlled terahertz spatial light modulators with graphene arrays,” presented at the IEEE MTT-S International Microwave Symposium (IMS), San Francisco, CA, 2016, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/54963.