scholarly journals Room Temperature Direct and Heterodyne Detection of 0.28–0.69-THz Waves Based on GaN 2-DEG Unipolar Nanochannels

2016 ◽  
Vol 63 (1) ◽  
pp. 353-359 ◽  
Author(s):  
Carlos Daher ◽  
Jeremie Torres ◽  
Ignacio Iniguez-de-la-Torre ◽  
Philippe Nouvel ◽  
Luca Varani ◽  
...  
Keyword(s):  
Room Temperature ◽  
Heterodyne Detection ◽  
Thz Waves

scholarly journals Giant controllable gigahertz to terahertz nonlinearities in superlattices

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
M. F. Pereira ◽  
V. Anfertev ◽  
Y. Shevchenko ◽  
V. Vaks
Keyword(s):  
Room Temperature ◽  
Current Flow ◽  
Excitation Power ◽  
Design Tool ◽  
Heterodyne Detection ◽  
Nonlinear Susceptibility ◽  
Optical Nonlinearities ◽  
Clear Cut ◽  
Thz Range ◽  
Predictive Design

Abstract Optical nonlinearities are of perpetual importance, notably connected with emerging new materials. However, they are difficult to exploit in the gigahertz–terahertz (GHz–THz) range at room temperature and using low excitation power. Here, we present a clear-cut theoretical and experimental demonstration of real time, low power, room temperature control of GHz–THz nonlinearities. The nonlinear susceptibility concept, successful in most materials, cannot be used here and we show in contrast, a complex interplay between applied powers, voltages and asymmetric current flow, delivering giant control and enhancement of the nonlinearities. Semiconductor superlattices are used as nonlinear sources and as mixers for heterodyne detection, unlocking their dual potential as compact, room temperature, controllable sources and detectors. The low input powers and voltages applied are within the range of compact devices, enabling the practical extension of nonlinear optics concepts to the GHz–THz range, under controlled conditions and following a predictive design tool.

PROGRESS ON WIDELY-TUNABLE MONOCHROMATIC THz SOURCES AND ROOM-TEMPERATURE DETECTIONS OF THz WAVES

2006 ◽  
Vol 15 (01) ◽  
pp. 89-111 ◽  
Author(s):  
YUJIE J. DING ◽  
WEI SHI
Keyword(s):  
Peak Power ◽  
Room Temperature ◽  
Difference Frequency Generation ◽  
Infrared Laser ◽  
Output Wavelength ◽  
Infrared Laser Beam ◽  
Order Of Magnitude ◽  
Thz Sources ◽  
Thz Waves ◽  
Thz Power

We have further developed widely-tunable monochromatic THz sources. These sources are based on difference-frequency generation (DFG) in GaSe and GaP crystals. Using a 47 mm long GaSe crystal the output wavelength was tuned in the range from 66.5 to 5664 μm (from 150 to 1.77 cm-1) with the peak powers reaching 389 W. This record-high power corresponds to a conversion efficiency of ~0.1%. On the other hand, using a 20 mm long GaP crystal the output wavelength was tuned in the range 71.1–2830 μm whereas the highest peak power was 15.6 W. The advantage of using GaP over GaSe is obvious: crystal rotation is no longer required for wavelength tuning. Instead, one just needs to tune the wavelength of one mixing beam within the bandwidth of as narrow as 15.3 nm. Most recently, we implemented a new scheme for detecting THz waves based on upconversion at room temperature, i.e. by mixing the THz wave with an infrared laser beam, we observed the upconverted signal at a wavelength just slightly longer than that of the infrared laser. To date the detectable THz power is just an order of magnitude higher than that for a bolometer. This scheme allows us to measure the pulse energy density, wavelength, linewidth, and pulse width of a THz beam at room temperature. Using our widely-tunable monochromatic THz beam, we directly measured the absorption spectra of three different families of the homologues of the chemical vapors.

Nonlinear nanochannels for room temperature terahertz heterodyne detection

2013 ◽  
Vol 28 (12) ◽  
pp. 125024 ◽  
Author(s):  
Jeremie Torres ◽  
Philippe Nouvel ◽  
Alexandre Penot ◽  
Luca Varani ◽  
Paul Sangaré ◽  
...  
Keyword(s):  
Room Temperature ◽  
Heterodyne Detection

Terahertz Plasmonics and Nano-Carbon Electronics for Nano-Micro Sensing and Imaging

2018 ◽  
Vol 12 (1) ◽  
pp. 87-96 ◽  
Author(s):  
Xiangying Deng ◽  
Yukio Kawano ◽  
◽  
Keyword(s):  
Room Temperature ◽  
Three Dimensional ◽  
Plasmonic Structures ◽  
Nano Carbon ◽  
Thz Sensing ◽  
Thz Detector ◽  
Flexible Imaging ◽  
Bull's Eye ◽  
Thz Waves ◽  
Carbon Based

Sensing and imaging with THz waves is an active area of modern research in optical science and technology. There have been a number of studies for enhancing THz sensing technologies. In this paper, we review our recent development of THz plasmonic structures and carbon-based THz imagers. The plasmonic structures have strong possibilities of largely increasing detector sensitivity because of their outstanding properties of high transmission enhancement at a subwavelength aperture and local field concentration. We introduce novel plasmonic structures and their performance, including a Si-immersed bull’s-eye antenna and multi-frequency bull’s-eye antennas. The latter part of this paper explains carbon-based THz detectors and their applications in omni-directional flexible imaging. The use of carbon nanotube films has led to a room-temperature, flexible THz detector and has facilitated the visualization of samples with three-dimensional curvatures. The techniques described in this paper can be used effectively for THz sensing and imaging on a micro- and nano-scale.

Room-temperature semiconductor modulators for free-space signal transmission with THz waves

2004 ◽  
Author(s):  
Thomas Kleine-Ostmann ◽  
Klaus Pierz ◽  
G’nter Hein ◽  
Philip Dawson ◽  
Martin Koch
Keyword(s):  
Free Space ◽  
Room Temperature ◽  
Signal Transmission ◽  
Thz Waves
Sign in / Sign up

Export Citation Format

Share Document