Electronic control of extraordinary terahertz transmission through subwavelength metal hole arrays

Los Alamos National Laboratory, MPA-CINT, MS K771, Los Alamos, New Mexico 87545, USA.
Optics Express (Impact Factor: 3.49). 06/2008; 16(11):7641-8. DOI: 10.1364/OE.16.007641
Source: PubMed


We describe the electronic control of extraordinary terahertz transmission through subwavelength metal hole arrays fabricated on doped semiconductor substrates. The hybrid metal-semiconductor forms a Schottky diode structure, where the active depletion region modifies the substrate conductivity in real-time by applying an external voltage bias. This enables effective control of the resonance enhanced terahertz transmission. Our proof of principle device achieves an intensity modulation depth of 52% by changing the voltage bias between 0 and 16 volts. Further optimization may result in improvement of device performance and practical applications. This approach can be also translated to the other optical frequency ranges.

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