scholarly journals On-chip Fourier-transform spectrometer based on spatial heterodyning tuned by thermo-optic effect

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Miguel Montesinos-Ballester ◽  
Qiankun Liu ◽  
Vladyslav Vakarin ◽  
Joan Manel Ramirez ◽  
Carlos Alonso-Ramos ◽  
...  
Keyword(s):  
Fourier Transform ◽  
Medical Diagnostics ◽  
Spatial Multiplexing ◽  
Optical Path ◽  
Fine Tuning ◽  
Path Delay ◽  
Mid Infrared ◽  
Wide Range ◽  
Infrared Spectral ◽  
On Chip

Abstract Miniaturized optical spectrometers providing broadband operation and fine resolution have an immense potential for applications in remote sensing, non-invasive medical diagnostics and astronomy. Indeed, optical spectrometers working in the mid-infrared spectral range have garnered a great interest for their singular capability to monitor the main absorption fingerprints of a wide range of chemical and biological substances. Fourier-transform spectrometers (FTS) are a particularly interesting solution for the on-chip integration due to their superior robustness against fabrication imperfections. However, the performance of current on-chip FTS implementations is limited by tradeoffs in bandwidth and resolution. Here, we propose a new FTS approach that gathers the advantages of spatial heterodyning and optical path tuning by thermo-optic effect to overcome this tradeoff. The high resolution is provided by spatial multiplexing among different interferometers with increasing imbalance length, while the broadband operation is enabled by fine tuning of the optical path delay in each interferometer harnessing the thermo-optic effect. Capitalizing on this concept, we experimentally demonstrate a mid-infrared SiGe FTS, with a resolution better than 15 cm−1 and a bandwidth of 603 cm−1 near 7.7 μm wavelength with a 10 MZI array. This is a resolution comparable to state-of-the-art on-chip mid-infrared spectrometers with a 4-fold bandwidth increase with a footprint divided by a factor two.

scholarly journals A CMOS Compatible Pyroelectric Mid-Infrared Detector Based on Aluminium Nitride

Sensors ◽  
2019 ◽  
Vol 19 (11) ◽  
pp. 2513 ◽  
Author(s):  
Christian Ranacher ◽  
Cristina Consani ◽  
Andreas Tortschanoff ◽  
Lukas Rauter ◽  
Dominik Holzmann ◽  
...  
Keyword(s):  
Infrared Detector ◽  
Aluminium Nitride ◽  
Co2 Absorption ◽  
Absorption Region ◽  
Mid Infrared ◽  
Infrared Spectral Range ◽  
Wide Range ◽  
Infrared Spectral ◽  
Pyroelectric Material ◽  
Cmos Compatible

The detection of infrared radiation is of great interest for a wide range of applications, such as absorption sensing in the infrared spectral range. In this work, we present a CMOS compatible pyroelectric detector which was devised as a mid-infrared detector, comprising aluminium nitride (AlN) as the pyroelectric material and fabricated using semiconductor mass fabrication processes. To ensure thermal decoupling of the detector, the detectors are realized on a Si3N4/SiO2 membrane. The detectors have been tested at a wavelength close to the CO2 absorption region in the mid-infrared. Devices with various detector and membrane sizes were fabricated and the influence of these dimensions on the performance was investigated. The noise equivalent power of the first demonstrator devices connected to a readout circuit was measured to be as low as 5.3 × 10 − 9 W / Hz .

A High-Precision Wide Range On-Chip Path Delay Measurement

2014 ◽  
Vol 11 (9) ◽  
pp. 450-454
Author(s):  
Neelufar Naheed Saudagar ◽  
◽  
Seema Deshmukh
Keyword(s):  
High Precision ◽  
Path Delay ◽  
Delay Measurement ◽  
Wide Range ◽  
On Chip

scholarly journals Surface-enhanced mid-infrared absorption spectroscopy using miniaturized-disc metasurface

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Mitchell Semple ◽  
Ashwin K. Iyer
Keyword(s):  
Infrared Spectroscopy ◽  
Signal To Noise Ratio ◽  
Low Cost ◽  
Unit Cell ◽  
Mid Infrared ◽  
Wide Range ◽  
Surface Enhanced ◽  
Identification Measurements ◽  
Vibrational Bands ◽  
On Chip

AbstractSurface-enhanced infrared spectroscopy is an important technique for improving the signal-to-noise ratio of spectroscopic material identification measurements in the mid-infrared fingerprinting region. However, the lower bound of the fingerprinting region receives much less attention due to a scarcity of transparent materials, more expensive sources, and weaker plasmonic effects. In this paper, we present a miniaturized metasurface unit cell for surface-enhanced infrared spectroscopy of the 15-$$\upmu$$ μ m vibrational band of CO$$_{2}$$ 2 . The unit cell consists of a gold disc, patterned along the edge with fine gaps/wires to create a resonant metamaterial liner. In simulation, our plasmonic metamaterial-lined disc achieves greater than $$4\times$$ 4 × the average field intensity enhancement of a comparable dipole array and a miniaturized size of $$\lambda _0/5$$ λ 0 / 5 using complex, 100-nm features that are patterned using 100-kV electron-beam lithography. In a simple experiment, the metamaterial-lined disc metasurface shows a high tolerance to fabrication imperfections and enhances the absorption of CO$$_{2}$$ 2 at 15 $$\upmu$$ μ m. The resonant wavelength and reflection magnitude can be tuned over a wide range by adjusting the liner feature sizes and the metasurface array pitch to target other vibrational bands. This work is a step toward low-cost, more compact on-chip integrated gas sensors.

scholarly journals Electro-Absorption Modulation in GeSn Alloys for Wide-Spectrum Mid-Infrared Applications

2021 ◽  
Author(s):  
Yun-Da Hsieh ◽  
Jun-Han Lin ◽  
Richard Soref ◽  
Greg Sun ◽  
Hung-Hsiang Cheng ◽  
...  
Keyword(s):  
Integrated Circuits ◽  
Wide Spectrum ◽  
Complementary Metal Oxide Semiconductor ◽  
Oxide Semiconductor ◽  
Optical Modulation ◽  
Bandgap Energy ◽  
Optical Modulators ◽  
Mid Infrared ◽  
Wide Range ◽  
On Chip

Abstract Si-based electronic-photonic integrated circuits (EPICs), which are compatible with state-of-the-art complementary metal-oxide-semiconductor (CMOS) processes, offer promising opportunities for on-chip mid-infrared (MIR) photonic systems. However, the lack of efficient MIR optical modulators on Si hinders the utilization of MIR EPICs. Here, we clearly demonstrate the Franz-Keldysh (FK) effect in GeSn alloys and achieve on-Si MIR electro-absorption optical modulation using GeSn heterostructures. Our experimental and theoretical results verify that the direct bandgap energy of GeSn can be widely tuned by varying the Sn content, thereby realizing wavelength-tunable optical modulation in the MIR range with a figure-of-merit of Δα /α0 (FOM) greater than 1.5 and a broadband operating range greater than 140 nm. In contrast to conventional silicon-photonic modulators based on the plasma dispersion effect, our GeSn heterostructure demonstrates practical and effective FK MIR optical modulation on Si and helps unlock the potential of MIR EPICs for a wide range of applications.

scholarly journals Long-term intercomparison of MIPAS additional species ClONO2, N2O5, CFC-11, and CFC-12 with MIPAS-B measurements

2014 ◽  
Author(s):  
Gerald Wetzel ◽  
Hermann Oelhaf ◽  
Felix Friedl-Vallon ◽  
Anne Kleinert ◽  
Guido Maucher ◽  
...  
Keyword(s):  
Fourier Transform ◽  
Spectral Region ◽  
Michelson Interferometer ◽  
Additional Species ◽  
Mid Infrared ◽  
Infrared Spectral Region ◽  
Atmospheric Sounding ◽  
Infrared Spectral

The Michelson Interferometer for Passive Atmospheric Sounding (MIPAS) aboard the environmental satellite ENVISAT is a limb-viewing Fourier-transform emission spectrometer working in the mid-infrared spectral region between 685 cm<sup>-1</sup> and 2410 cm<sup>-1</sup> [...]

scholarly journals Biosensors in Health Care: The Milestones Achieved in Their Development towards Lab-on-Chip-Analysis

2016 ◽  
Vol 2016 ◽  
pp. 1-12 ◽  
Author(s):  
Suprava Patel ◽  
Rachita Nanda ◽  
Sibasish Sahoo ◽  
Eli Mohapatra
Keyword(s):  
Point Of Care ◽  
Medical Diagnostics ◽  
Point Of Care Testing ◽  
Lab On Chip ◽  
Testing Facility ◽  
Wide Range ◽  
On Chip ◽  
Huge Challenge ◽  
Chip Analysis ◽  
Higher Sensitivity

Immense potentiality of biosensors in medical diagnostics has driven scientists in evolution of biosensor technologies and innovating newer tools in time. The cornerstone of the popularity of biosensors in sensing wide range of biomolecules in medical diagnostics is due to their simplicity in operation, higher sensitivity, ability to perform multiplex analysis, and capability to be integrated with different function by the same chip. There remains a huge challenge to meet the demands of performance and yield to its simplicity and affordability. Ultimate goal stands for providing point-of-care testing facility to the remote areas worldwide, particularly the developing countries. It entails continuous development in technology towards multiplexing ability, fabrication, and miniaturization of biosensor devices so that they can provide lab-on-chip-analysis systems to the community.

scholarly journals Silicon-Based Multilayer Waveguides for Integrated Photonic Devices from the Near to Mid Infrared

2021 ◽  
Vol 11 (3) ◽  
pp. 1227
Author(s):  
Iñaki López García ◽  
Mario Siciliani de Cumis ◽  
Davide Mazzotti ◽  
Iacopo Galli ◽  
Pablo Cancio Pastor ◽  
...  
Keyword(s):  
Photonic Devices ◽  
Visible Range ◽  
Experimental Characterization ◽  
Mid Infrared ◽  
Wide Range ◽  
Infrared Spectral ◽  
Silicon Based ◽  
Optical Behavior ◽  
532 Nm

Advancements in spectroscopy, quantum optics, communication, and sensing require new classes of integrated photonic devices to host a wide range of non-linear optical processes involving wavelengths from the visible to the infrared. In this framework, waveguide (WG) structures designed with innovative geometry and materials can play a key role. We report both finite element modeling and experimental characterization of silicon nitride multilayer WGs from the visible to the mid-infrared spectral regions. The simulations evaluated optical behavior and mechanical stress as a function of number of WG layers and photonic structure dimensions. WGs were optimized for waveguiding at 1550 nm and 2640 nm. Experimental characterization focused on optical behavior and coupling losses from 532 nm to 2640 nm. Measured losses in WGs indicate a quasi-perfect waveguiding behavior in the IR range (with losses below 6 dB), with a relevant increase (up to 20 dB) in the visible range.

scholarly journals Source brightness fluctuation correction of solar absorption fourier transform mid infrared spectra

2011 ◽  
Vol 4 (6) ◽  
pp. 1045-1051 ◽  
Author(s):  
T. Ridder ◽  
T. Warneke ◽  
J. Notholt
Keyword(s):  
Fourier Transform ◽  
Spectral Region ◽  
Near Infrared ◽  
Infrared Spectrometry ◽  
Solar Absorption ◽  
Mid Infrared ◽  
Infrared Spectral Region ◽  
Infrared Measurements ◽  
Infrared Spectral ◽  
Brightness Fluctuation

Abstract. The precision and accuracy of trace gas observations using solar absorption Fourier Transform infrared spectrometry depend on the stability of the light source. Fluctuations in the source brightness, however, cannot always be avoided. Current correction schemes, which calculate a corrected interferogram as the ratio of the raw DC interferogram and a smoothed DC interferogram, are applicable only to near infrared measurements. Spectra in the mid infrared spectral region below 2000 cm−1 are generally considered uncorrectable, if they are measured with a MCT detector. Such measurements introduce an unknown offset to MCT interferograms, which prevents the established source brightness fluctuation correction. This problem can be overcome by a determination of the offset using the modulation efficiency of the instrument. With known modulation efficiency the offset can be calculated, and the source brightness correction can be performed on the basis of offset-corrected interferograms. We present a source brightness fluctuation correction method which performs the smoothing of the raw DC interferogram in the interferogram domain by an application of a running mean instead of high-pass filtering the corresponding spectrum after Fourier transformation of the raw DC interferogram. This smoothing can be performed with the onboard software of commercial instruments. The improvement of MCT spectra and subsequent ozone profile and total column retrievals is demonstrated. Application to InSb interferograms in the near infrared spectral region proves the equivalence with the established correction scheme.

Sign in / Sign up

Export Citation Format

Share Document