Survey
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Download Novel Periodic Solid State Devices for Terahertz Emission
Document related concepts
Transcript
Novel Periodic Solid State Devices for Terahertz Emission and Detection NIRT 0609146 : Nanostructure Components for Terahertz Spectroscopy on a Chip Greg Dyer, Jesse. Crossno*, James. Kally*, Kavir. Dass*, S.J. Allen, Gehong Zeng, and John Bowers (UC Santa Barbara) Peter Robrish, Rick Trutna, Dan Mars and Greg Lee (Agilent) * Undergrad research interns Greg Aizin (City College New York) Eric Shaner, Mike Wanke and John Reno (Sandia) Objectives Voltage Controlled Lateral Barrier DC & GHz Bias Scheme – Terahertz Emission – Terahertz gain in an electrically sold state device – Room temperature operation – Coherent radiation – mW power – Terahertz Detection – Narrow-band response – Tunability – LN2 or higher T operation T = 20 K – Ring and disk metal cladded resonators –Super-superlatice includes n+ doped layers to mitigate electric field domain formation Terahertz Spectroscopy Filling the Terahertz Source Gap – Quantum cascade lasers (QCLs) require cryogenic temperatures – Barrier gate biased produces potential barrier in 2D channel – Gate controls barrier and by diode-like activation model – Electronics have low output power at high THz frequencies Resonant Response – Bloch oscillator has potential to provide tunable terahertz radiation at room temperature T = 20 K, VBG = -850 mV –InSb or Si composite bolometer to detect emission (left) Bloch Oscillations and the Stark Ladder – Terahertz interferometer to analyze spectral content (right) – Under positive bias, a sharp resonant feature is present Plasmonic Terahertz Detectors –Equivalent views: Scattering from Bragg planes (left) or Stark ladder (right) – Under negative bias, appears to be double resonance Hot Electron Bolometric Response ‘opening’ of T = 20 K, n = 420 GHz –Gain without inversion Harmonic Generation and Parametric Gain – Grating gate offers tunability of electron density – Additional barrier gate beyond pinchoff increases responsivity when biased – Superlattices are highly non-linear materials – DC and/or RF bias scheme for harmonic generation (left), parametric gain (right), or LSA mode operation Center for Terahertz Science and Technology UC Santa Barbara Sandia is a multiprogram laboratory operated by Sandia Corporation, a Lockheed Martin Company, for the United States Department of Energy under contract DE-AC04-94AL85000.
