scholarly journals Homodyne Solid-State Biased Coherent Detection of Ultra-Broadband Terahertz Pulses with Static Electric Fields

Nanomaterials ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 283
Author(s):  
Alessandro Tomasino ◽  
Riccardo Piccoli ◽  
Yoann Jestin ◽  
Boris Le Drogoff ◽  
Mohamed Chaker ◽  
...  

We present an innovative implementation of the solid-state-biased coherent detection (SSBCD) technique, which we have recently introduced for the reconstruction of both amplitude and phase of ultra-broadband terahertz pulses. In our previous works, the SSBCD method has been operated via a heterodyne scheme, which involves demanding square-wave voltage amplifiers, phase-locked to the THz pulse train, as well as an electronic circuit for the demodulation of the readout signal. Here, we demonstrate that the SSBCD technique can be operated via a very simple homodyne scheme, exploiting plain static bias voltages. We show that the homodyne SSBCD signal turns into a bipolar transient when the static field overcomes the THz field strength, without the requirement of an additional demodulating circuit. Moreover, we introduce a differential configuration, which extends the applicability of the homodyne scheme to higher THz field strengths, also leading a two-fold improvement of the dynamic range compared to the heterodyne counterpart. Finally, we demonstrate that, by reversing the sign of the static voltage, it is possible to directly retrieve the absolute THz pulse polarity. The homodyne configuration makes the SSBCD technique of much easier access, leading to a vast range of field-resolved applications.

Optica ◽  
2017 ◽  
Vol 4 (11) ◽  
pp. 1358 ◽  
Author(s):  
Alessandro Tomasino ◽  
Anna Mazhorova ◽  
Matteo Clerici ◽  
Marco Peccianti ◽  
Sze-Phing Ho ◽  
...  

Author(s):  
Alessandro Tomasino ◽  
Anna Mazhorova ◽  
Matteo Clerici ◽  
Marco Peccianti ◽  
Sze-Phing Ho ◽  
...  

Author(s):  
Anna Mazhorova ◽  
Sze-Ping Ho ◽  
Matteo Clerici ◽  
Marco Peccianti ◽  
Alessia Pasquazi ◽  
...  

Author(s):  
Martin Peckerar ◽  
Anastasios Tousimis

Solid state x-ray sensing systems have been used for many years in conjunction with scanning and transmission electron microscopes. Such systems conveniently provide users with elemental area maps and quantitative chemical analyses of samples. Improvements on these tools are currently sought in the following areas: sensitivity at longer and shorter x-ray wavelengths and minimization of noise-broadening of spectral lines. In this paper, we review basic limitations and recent advances in each of these areas. Throughout the review, we emphasize the systems nature of the problem. That is. limitations exist not only in the sensor elements but also in the preamplifier/amplifier chain and in the interfaces between these components.Solid state x-ray sensors usually function by way of incident photons creating electron-hole pairs in semiconductor material. This radiation-produced mobile charge is swept into external circuitry by electric fields in the semiconductor bulk.


2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Lars Liebermeister ◽  
Simon Nellen ◽  
Robert B. Kohlhaas ◽  
Sebastian Lauck ◽  
Milan Deumer ◽  
...  

AbstractBroadband terahertz spectroscopy enables many promising applications in science and industry alike. However, the complexity of existing terahertz systems has as yet prevented the breakthrough of this technology. In particular, established terahertz time-domain spectroscopy (TDS) schemes rely on complex femtosecond lasers and optical delay lines. Here, we present a method for optoelectronic, frequency-modulated continuous-wave (FMCW) terahertz sensing, which is a powerful tool for broadband spectroscopy and industrial non-destructive testing. In our method, a frequency-swept optical beat signal generates the terahertz field, which is then coherently detected by photomixing, employing a time-delayed copy of the same beat signal. Consequently, the receiver current is inherently phase-modulated without additional modulator. Owing to this technique, our broadband terahertz spectrometer performs (200 Hz measurement rate, or 4 THz bandwidth and 117 dB peak dynamic range with averaging) comparably to state-of-the-art terahertz-TDS systems, yet with significantly reduced complexity. Thickness measurements of multilayer dielectric samples with layer-thicknesses down to 23 µm show its potential for real-world applications. Within only 0.2 s measurement time, an uncertainty of less than 2 % is achieved, the highest accuracy reported with continuous-wave terahertz spectroscopy. Hence, the optoelectronic FMCW approach paves the way towards broadband and compact terahertz spectrometers that combine fiber optics and photonic integration technologies.


2005 ◽  
Vol 87 (15) ◽  
pp. 151501 ◽  
Author(s):  
B. H. Kolner ◽  
P. M. Conklin ◽  
R. A. Buckles ◽  
N. K. Fontaine ◽  
R. P. Scott

Sign in / Sign up

Export Citation Format

Share Document