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1. Nonlinear dynamics in multimode optical fibers

Author

Wabnitz, Stefan, Tonello, Alessandro, Couderc, Vincent, Barthélémy, Alain, Millot, Guy, Krupa, Katarzyna, Modotto, Daniele, Razeghi, Manijeh, Brown, Gail, Leo, Giuseppe, Lewis, Jay, univesité de brescia, Department of Information Engineering, Photonique Fibre et Sources Cohérentes (XLIM-PHOT), XLIM (XLIM), Université de Limoges (UNILIM)-Centre National de la Recherche Scientifique (CNRS)-Université de Limoges (UNILIM)-Centre National de la Recherche Scientifique (CNRS), Laboratoire Interdisciplinaire Carnot de Bourgogne (LICB), Université de Bourgogne (UB)-Centre National de la Recherche Scientifique (CNRS), Università degli Studi di Brescia [Brescia], Northwestern University [Evanston], Laboratoire Matériaux et Phénomènes Quantiques (MPQ (UMR_7162)), Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), and Brescia University

Subjects
Physics, [PHYS.PHYS.PHYS-OPTICS]Physics [physics]/Physics [physics]/Optics [physics.optics], Multi-mode optical fiber, Kerr effect, Optical fiber, business.industry, FOS: Physical sciences, Physics::Optics, Nonlinear optics, 01 natural sciences, Supercontinuum, law.invention, 010309 optics, Optics, law, Fiber laser, 0103 physical sciences, Physics::Accelerator Physics, Light beam, 010306 general physics, business, ComputingMilieux_MISCELLANEOUS, Beam (structure), Optics (physics.optics), Physics - Optics
Abstract

We overview recent advances in the research on spatiotemporal beam shaping in nonlinear multimode optical fibers. An intense light beam coupled to a graded index (GRIN) highly multimode fiber undergoes a series of complex nonlinear processes when its power grows larger. Among them, the lowest threshold effect is the Kerr-induced beam self-cleaning, that redistributes most of the beam energy into a robust bell-shaped beam close to the fundamental mode. At higher powers a series of spectral sidebands is generated, thanks to the phase matching induced by the long period grating due to the periodic self-imaging of the beam and the Kerr effect. Subsequently a broadband and spectrally flat supercontinuum is generated, extending from the visible to the mid-infrared.

Published
2018

4. Localized surface plasmon fiber device coated with carbon nanotubes for the specific detection of CO2

Author

Razeghi, Manijeh, Temple, Dorota S., Brown, Gail J., Allsop, Thomas D.P., Arif, Raz, Neal, Ron, Kalli, Kyriacos, Kundrát, Vojtech, Rozhin, Alex, Culverhouse, Philip, Webb, David J., Razeghi, Manijeh, Temple, Dorota S., Brown, Gail J., Allsop, Thomas D.P., Arif, Raz, Neal, Ron, Kalli, Kyriacos, Kundrát, Vojtech, Rozhin, Alex, Culverhouse, Philip, and Webb, David J.

Abstract

We explored the potential of a carbon nanotube (CNT) coating working in conjunction with a recently developed localized surface plasmon (LSP) device (based upon a nanostructured thin film consisting of of nano-wires of platinum) with ultra-high sensitivity to changes in the surrounding index. The uncoated LSP sensor’s transmission resonances exhibited a refractive index sensitivity of Δλ/Δn ~ -6200nm/RIU and ΔΙ/Δn ~5900dB/RIU, which is the highest reported spectral sensitivity of a fiber optic sensor to bulk index changes within the gas regime. The complete device provides the first demonstration of the chemically specific gas sensing capabilities of CNTs utilizing their optical characteristics. This is proven by investigating the spectral response of the sensor before and after the adhesion of CNTs to alkane gases along with carbon dioxide. The device shows a distinctive spectral response in the presence of gaseous CO2 over and above what is expected from general changes in the bulk refractive index. This fiber device yielded a limit of detection of 150ppm for CO2 at a pressure of one atmosphere. Additionally the adhered CNTs actually reduce sensitivity of the device to changes in bulk refractive index of the surrounding medium. The polarization properties of the LSP sensor resonances are also investigated and it is shown that there is a reduction in the overall azimuthal polarization after the CNTs are applied. These optical devices offer a way of exploiting optically the chemical selectivity of carbon nanotubes, thus providing the potential for real-world applications in gas sensing in many inflammable and explosive environments.

Published
2015

26. Quantum well infrared detection devices

Author

Liu, Hui C., primary, Song, Chunying, additional, Shen, Aidong, additional, Dudek, Richard, additional, Gao, Ming, additional, Dupont, Emmanuel, additional, Wasilewski, Zbigniew R., additional, Buchanan, Margaret, additional, Wilson, P. H., additional, Robinson, Brad J., additional, Thompson, David A., additional, Brown, Gail J., additional, Szmulowicz, Frank, additional, and Ehret, James E., additional

Published
2001
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30. Type-II InAs/InGaSb SL photodetectors

Author

Lin, C.H. T., primary, Anselm, K. Alex, additional, Kuo, Chau-Hong, additional, Delaney, A. M., additional, Brown, Gail J., additional, Mahalingam, Krishnamur, additional, Saxler, Adam W., additional, Linville, Raymond J., additional, Szmulowicz, Frank, additional, and Nathan, Vaidya, additional

Published
2000
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41. Localized surface plasmon fiber device coated with carbon nanotubes for the specific detection of CO2

Author

Allsop, Thomas D.P., Arif, Raz, Neal, Ron, Kalli, Kyriacos, Kundrát, Vojtech, Rozhin, Alex, Culverhouse, Philip, Webb, David J., Razeghi, Manijeh, Temple, Dorota S., and Brown, Gail J.

Subjects
Physics::Optics
Abstract

We explored the potential of a carbon nanotube (CNT) coating working in conjunction with a recently developed localized surface plasmon (LSP) device (based upon a nanostructured thin film consisting of of nano-wires of platinum) with ultra-high sensitivity to changes in the surrounding index. The uncoated LSP sensor’s transmission resonances exhibited a refractive index sensitivity of Δλ/Δn ~ -6200nm/RIU and ΔΙ/Δn ~5900dB/RIU, which is the highest reported spectral sensitivity of a fiber optic sensor to bulk index changes within the gas regime. The complete device provides the first demonstration of the chemically specific gas sensing capabilities of CNTs utilizing their optical characteristics. This is proven by investigating the spectral response of the sensor before and after the adhesion of CNTs to alkane gases along with carbon dioxide. The device shows a distinctive spectral response in the presence of gaseous CO2 over and above what is expected from general changes in the bulk refractive index. This fiber device yielded a limit of detection of 150ppm for CO2 at a pressure of one atmosphere. Additionally the adhered CNTs actually reduce sensitivity of the device to changes in bulk refractive index of the surrounding medium. The polarization properties of the LSP sensor resonances are also investigated and it is shown that there is a reduction in the overall azimuthal polarization after the CNTs are applied. These optical devices offer a way of exploiting optically the chemical selectivity of carbon nanotubes, thus providing the potential for real-world applications in gas sensing in many inflammable and explosive environments.

Published
2015

42. Field test results of compound specific isotope analyzer based on quantum cascade lasers and hollow waveguide

Author

Andrei Deev, Sheng Wu, Razeghi, Manijeh, Tournié, Eric, and Brown, Gail J.

Subjects
chemistry.chemical_compound, Permeability (earth sciences), Materials science, chemistry, Isotope, Propane, Cascade, Analytical chemistry, Spectroscopy, Porosity, Oil shale, Methane
Abstract

The first of its kind Gas Chromatograph Infra Red Isotope Ratio (GC-IR2) instruments have been deployed to the field to help the identification of sweet spot during the shale gas exploration. The onsite measurement capability of the GC-IR2 along with its accuracy and speed helped the discovery of the fast dynamics of gas release from shale cuttings. The half life of the isotope change for methane, ethane and propane released from shale cuttings is closely related to the porosity and permeability of the specific shale reservoir, and could be as short as a one hour to a couple of days. Initial δ^(13)C values for methane could be extremely fractionated toward heavy ^(13)C species that values in the -20~

Published
2015

43. Chaotic behaviour of photonic crystals resonators

Author

Andrea Fratalocchi, A. Di Falco, Thomas F. Krauss, Changxu Liu, Razeghi, Manijeh, Tournié, Eric, Brown, Gail J., EPSRC, and University of St Andrews. School of Physics and Astronomy

Subjects
Physics, Optical resonators, business.industry, Chaotic resonators, NDAS, Chaotic, Physics::Optics, Silicon on insulator, Superradiance, Resonator, QC Physics, Photonic Crystals, Optoelectronics, business, Telecommunications, Energy harvesting, Quantum, QC, Computer Science::Databases, Photonic crystal
Abstract

We acknowledge support from the EPSRC (ADF, Fellowships No. EP/I004602/1 and No. EP/J004200/1) and KAUST (AF, Grant No. CRG-1-2012-FRA-005). We show here theoretically and experimentally how chaotic Photonic Crystal resonators can be used for en- ergy harvesting applications and the demonstration of fundamental theories, like the onset of superradiance in quantum systems. Publisher PDF

Published
2015

44. A field-deployable compound-specific isotope analyzer based on quantum cascade laser and hollow waveguide

Author

Andrei Deev, Sheng Wu, Razeghi, Manijeh, Tournié, Eric, and Brown, Gail J.

Subjects
Spectrum analyzer, Materials science, Resolution (mass spectrometry), business.industry, Single-mode optical fiber, Analytical chemistry, Mass spectrometry, Laser, law.invention, Optics, law, Cascade, Spectroscopy, business, Quantum cascade laser
Abstract

A field deployable Compound Specific Isotope Analyzer (CSIA) coupled with capillary chromatogrpahy based on Quantum Cascade (QC) lasers and Hollow Waveguide (HWG) with precision and chemical resolution matching mature Mass Spectroscopy has been achieved in our laboratory. The system could realize 0.3 per mil accuracy for ^(12)C/^(13)C for a Gas Chromatography (GC) peak lasting as short as 5 seconds with carbon molar concentration in the GC peak less than 0.5%. Spectroscopic advantages of HWG when working with QC lasers, i.e. single mode transmission, noiseless measurement and small sample volume, are compared with traditional free space and multipass spectroscopy methods.

Published
2013

45. Quantum cascade laser sensors for online gas chromatography

Author

Sheng Wu, Yongchun Tang, Andrei Deev, Razeghi, Manijeh, Sudharsanan, Rengarajan, and Brown, Gail J.

Subjects
Materials science, Resolution (mass spectrometry), business.industry, Laser, Noise (electronics), law.invention, symbols.namesake, Nuclear magnetic resonance, Modulation, law, Cascade, symbols, Optoelectronics, Physics::Atomic Physics, business, Quantum cascade laser, Doppler effect, Quantum
Abstract

We show that QC laser could improve capillary Gas Chromatography Infrared spectroscopy resolution significantly, i.e. both Doppler limited and Doppler free resolution could be achieved. To achieve these goals, we report our latest efforts in characterizing the tuning and noise properties of Quantum Cascade (QC) lasers; novel schemes on modulation to gain largest tuning range as well as on stabilizing and locking the QC lasers are proposed, and results presented.

Published
2011

46. Heterogeneous GaSb/SOI mid-infrared photonic integrated circuits for spectroscopic applications

Author

Jean-Baptiste Rodriguez, Laurent Cerutti, D. Van Thourhout, Günther Roelkens, Nannicha Hattasan, Eric Tournié, Razeghi, Manijeh, Sudharsanan, Rengarajan, Brown, Gail J, Department of Information Technology (INTEC), Universiteit Gent = Ghent University [Belgium] (UGENT), Institut d’Electronique et des Systèmes (IES), Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), Composants à Nanostructure pour le moyen infrarouge (NANOMIR), and Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)

Subjects
Technology and Engineering, Materials science, Silicon on insulator, 02 engineering and technology, bonding, law.invention, 020210 optoelectronics & photonics, law, 0202 electrical engineering, electronic engineering, information engineering, Wafer, SILICON, BCB, Silicon-on-insulator, Electronic circuit, SOI, Silicon photonics, business.industry, Heterogeneous integration, Photonic integrated circuit, 021001 nanoscience & nanotechnology, GaSb p-i-n photodetector, CMOS, [SPI.OPTI]Engineering Sciences [physics]/Optics / Photonic, Optoelectronics, Photonics, 0210 nano-technology, business, Waveguide
Abstract

International audience; Mid-infrared spectroscopy has gained significant importance in recent years as a detection technique for substances that absorb in this spectral region. Traditionally, a spectroscopic system consists of bulky equipment which is difficult to handle and incurs high cost. An integrated spectroscopic system would eliminate these disadvantages. GaSb-based active opto-electronic devices allow realizing mid-infrared light sources and detectors in the 2-3 mu m wavelength range for such integrated systems. Silicon photonics, based on Silicon-on-Insulator (SOI) waveguide circuits, on the other hand, is a well established technology based on high refractive index contrast waveguides, enabling ultra-compact passive integrated photonic circuits. Moreover, SOI waveguide circuit processing is compatible with CMOS processes. Hence, the integration of GaSb-based active devices onto SOI passive waveguide circuits potentially allows highly compact spectroscopic systems with a large degree of freedom in passive device design to improve the system performance. This approach has a high potential for several applications, e. g. an implantable glucose level monitor and gas sensing devices. In this paper, we report our work on the integration of GaSb-based epitaxy onto SOI waveguide circuits. The heterogeneous integration is based on an epitaxial layer transfer process using the polymer divinylsiloxane-benzocyclobutene (DVS-BCB) as a bonding agent. The process is performed by transferring the epitaxial layer to an SOI waveguide circuit wafer through a die-to-wafer bonding process. With this approach, a bonding layer of 150 nm thickness is easily achievable. We also report our results on the integration of waveguide-based GaSb p-i-n photodetectors coupled to SOI waveguide circuits using evanescent coupling, which show a responsivity higher than 0.4A/W. The design of active and passive structures and the overall fabrication process will also be discussed.

Published
2011

47. Novel broadband amplifier for mid-infrared semiconductor laser and applications in spectroscopy

Author

Zhenyu Li, Sheng Wu, Axel Scherer, Yongchun Tang, Andrei Deev, Razeghi, M., Sudharsanan, Rengarajan, and Brown, Gail J.

Subjects
Materials science, business.industry, Amplifier, Far-infrared laser, Laser, law.invention, Semiconductor laser theory, Semiconductor, Optics, law, Optoelectronics, Whispering-gallery wave, business, Quantum cascade laser, Spectroscopy
Abstract

An amplifier design for broadband Mid-IR buried-hetero (BH) structure epitaxial laser is presented, and external cavity design based on this amplifier is described. Spectroscopy results characterizing such single frequency lasers are demonstrated with whispering gallery mode CaF2 disc/ball, saturated absorption in hollow waveguide and direct chemical analysis in water.

Published
2010

48. Observation of whispering gallery modes in the mid-infrared with a quantum cascade laser: possible applications to nanoliter chemical sensing

Author

Andrei Deev, Sheng Wu, Razeghi, M., Sudharsanan, Rengarajan, and Brown, Gail J.

Subjects
Chemistry, business.industry, Mid infrared, Physics::Optics, law.invention, Semiconductor laser theory, Resonator, Optics, law, Prism coupling, Optoelectronics, Astrophysics::Earth and Planetary Astrophysics, Whispering-gallery wave, business, Quantum cascade laser, Astrophysics::Galaxy Astrophysics, Excitation
Abstract

Excitation of the whispering gallery modes (WGM) of a CaF_2 ball resonator is demonstrated at 4.5 micron with a pulsed Quantum Cascade laser. A prism coupling scheme for mid-infrared is described. Future applications of WGM resonators as hyphenated inline chromatography sensors are discussed.

Published
2009

49. Designing phonons for active use in terahertz devices

Author

James A. Gupta, C. Y. Song, H. C. Liu, Z. R. Wasilewski, Margaret Buchanan, Razeghi, Manijeh, Sudharsanan, Rengarajan, and Brown, Gail J.

Subjects
Materials science, optical phonon, Condensed Matter::Other, business.industry, Phonon, Terahertz radiation, quantum well, Physics::Optics, Fano resonance, Condensed Matter::Mesoscopic Systems and Quantum Hall Effect, Terahertz spectroscopy and technology, terahertz, Condensed Matter::Materials Science, Semiconductor, Quantum dot, Optoelectronics, business, Quantum well infrared photodetector, Quantum well
Abstract

Semiconductor nanostructures, such as quantum wells and quantum dots, are well known, and some have been incorporated in applications. Here we propose a new general approach to make use of polar optical phonons in quantum wells for terahertz (THz) devices. As the first example, we show the coupling of phonon and intersubband transition leading to Fano resonance in photocurrent spectra. We investigate the phenomenon experimentally in specially designed GaAs/AlGaAs quantum well infrared photodetectors. Finally, we discuss the future research and potentials., SPIE OPTO: Integrated Optoelectronic Devices, 24 January 2009, San Jose, CA, USA, Series: Proceedings of SPIE; no. 7222

Published
2009

50. Visible microdisk and photonic crystals lasers based on InGaP/InGaAlP system

Author

Zhaoyu Zhang, Axel Scherer, Kerry J. Vahala, Victor Liu, Ting Hong, Lan Yang, Razeghi, Manijeh, and Brown, Gail J.

Subjects
Mode volume, Materials science, business.industry, Nanophotonics, Physics::Optics, Laser, Vertical-cavity surface-emitting laser, law.invention, Indium gallium phosphide, chemistry.chemical_compound, Optics, chemistry, law, Optoelectronics, Photonics, business, Quantum well, Photonic crystal
Abstract

We describe the performance of submicron microdisk and photonic crystal lasers fabricated within InGaP/InGaAlP quantum well material. The smallest lasers, with diameters of approximately 600 nm, feature ultra-small mode volumes and exhibit single mode operation at low threshold powers. Their small cavity volumes of approximately 0.03 μm 3 for microdisk lasers and 0.01 μm 3 for photonic crystal lasers enable them to be used as spectroscopic sources. Here we demonstrate the fabrication and characterization of visible, monolithically fabricated, submicron mode volume lasers.

Published
2007

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