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Zhi Y, Lininger A, Strangi G. Manipulating random lasing correlations in doped liquid crystals. OPTICS LETTERS 2024; 49:1309-1312. [PMID: 38427000 DOI: 10.1364/ol.516290] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/18/2023] [Accepted: 02/13/2024] [Indexed: 03/02/2024]
Abstract
Random lasers are highly configurable light sources that are promising for imaging and photonic integration. In this study, random lasing action was generated by optically pumping N-(4-methoxybenzylidene)-4-butylaniline (MBBA) liquid crystals infiltrated with gold nanoparticles and a laser dye (pyrromethene 597 (PM597)). By varying the pump energy near a lasing threshold, we show that it is possible to control intensity correlations between random lasing modes. The correlations in the system were phenomenologically characterized using the Levy statistics of the emission spectrum survival function. We also find that correlations and persistence of lasing action are correlated. These results demonstrate the possibility to dynamically control a key physical feature of random lasers, which may find applications in biomedical settings and network communications.
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2
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Gayathri R, Suchand Sandeep CS, Vijayan C, Murukeshan VM. Lasing from Micro- and Nano-Scale Photonic Disordered Structures for Biomedical Applications. NANOMATERIALS (BASEL, SWITZERLAND) 2023; 13:2466. [PMID: 37686974 PMCID: PMC10490388 DOI: 10.3390/nano13172466] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/26/2023] [Revised: 08/24/2023] [Accepted: 08/29/2023] [Indexed: 09/10/2023]
Abstract
A disordered photonic medium is one in which scatterers are distributed randomly. Light entering such media experiences multiple scattering events, resulting in a "random walk"-like propagation. Micro- and nano-scale structured disordered photonic media offer platforms for enhanced light-matter interaction, and in the presence of an appropriate gain medium, coherence-tunable, quasi-monochromatic lasing emission known as random lasing can be obtained. This paper discusses the fundamental physics of light propagation in micro- and nano-scale disordered structures leading to the random lasing phenomenon and related aspects. It then provides a state-of-the-art review of this topic, with special attention to recent advancements of such random lasers and their potential biomedical imaging and biosensing applications.
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Affiliation(s)
- R. Gayathri
- Centre for Optical and Laser Engineering, School of Mechanical and Aerospace Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore 639798, Singapore; (R.G.); (C.S.S.S.)
| | - C. S. Suchand Sandeep
- Centre for Optical and Laser Engineering, School of Mechanical and Aerospace Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore 639798, Singapore; (R.G.); (C.S.S.S.)
| | - C. Vijayan
- Department of Physics, Indian Institute of Technology Madras, Chennai 600036, India
| | - V. M. Murukeshan
- Centre for Optical and Laser Engineering, School of Mechanical and Aerospace Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore 639798, Singapore; (R.G.); (C.S.S.S.)
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3
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Zhang SY, Wang YF, Shen D, Luo DB, Zheng ZG. Deflecting and routing nematicons via orientation programmable liquid crystal array. OPTICS EXPRESS 2023; 31:20955-20964. [PMID: 37381207 DOI: 10.1364/oe.486203] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/23/2023] [Accepted: 05/15/2023] [Indexed: 06/30/2023]
Abstract
By designing a liquid crystal cell with comb electrode structure, the alignment modulation of nematic liquid crystal in the cell can be realized after the electric field is applied. In different orientation regions, the incident laser beam can deflect at different angles. At the same time, by changing the incident angle of the laser beam, the reflection modulation of the laser beam on the interface of the liquid crystal molecular orientation change can be realized. Based on the above discussion, we then demonstrate the modulation of liquid crystal molecular orientation arrays on nematicon pairs. In different orientation regions of liquid crystal molecules, nematicon pairs can exhibit various combinations of deflections, and these deflection angles are modulable under external fields. Deflection and modulation of nematicon pairs have potential applications in optical routing and optical communication.
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4
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Azmi AN, Wan Ismail WZ, Abu Hassan H, Halim MM, Zainal N, Muskens OL, Wan Ahmad Kamil WM. Review of Open Cavity Random Lasers as Laser-Based Sensors. ACS Sens 2022; 7:914-928. [PMID: 35377613 DOI: 10.1021/acssensors.1c02749] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
In this review, the concept of open cavity lasing for ultrasensitive sensing is explored, specifically in driving important innovations as laser-based biosensors─a field mostly dominated by fluorescence-based sensing. Laser-based sensing exhibits higher signal amplification and lower signal-to-noise ratio due to narrow emission lines as well as high sensitivity due to nonlinear components. The versatility of open cavity random lasers for probing analytes directly which is ultrasensitive to small changes in chemical composition and temperature fluctuations paves the path of utilizing narrow emission lines for advanced sensing. The concept of random lasing is first explained followed by a comparison of the different lasing threshold that has been reported. This is followed by a survey of reports on laser-based sensing and more specifically as biosensors. Finally, a perspective on the way forward for open cavity laser-based sensing is put forth.
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Affiliation(s)
| | - Wan Zakiah Wan Ismail
- Faculty of Engineering and Built Environment, Universiti Sains Islam Malaysia, 71800, Nilai, Negeri Sembilan, Malaysia
| | - Haslan Abu Hassan
- School of Physics, Universiti Sains Malaysia, 11800 Penang, Malaysia
| | - Mohd Mahadi Halim
- School of Physics, Universiti Sains Malaysia, 11800 Penang, Malaysia
| | - Norzaini Zainal
- Institute of Nano Optoelectronics Research and Technology (INOR), Universiti Sains Malaysia, 11800, Penang, Malaysia
| | - Otto L. Muskens
- Physics and Astronomy, Faculty of Physical Sciences and Engineering, University of Southampton, Highfield, Southampton SO17 1BJ, United Kingdom
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5
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Special Issue on Light Beams in Liquid Crystals. APPLIED SCIENCES-BASEL 2022. [DOI: 10.3390/app12073668] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
The study of propagating light beams in liquid crystals, i [...]
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6
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Interactions of Self-Localised Optical Wavepackets in Reorientational Soft Matter. APPLIED SCIENCES-BASEL 2022. [DOI: 10.3390/app12052607] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/10/2022]
Abstract
The interaction of optical solitary waves in nematic liquid crystals, nematicons and vortices, with other nematicons and localised structures, such as refractive index changes, is reviewed. Such interactions are shown to enable simple routing schemes as a basis for all-optical guided wave signal manipulation.
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7
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Abstract
We carry out an experimental campaign to investigate the nonlinear self-defocusing propagation of singular light beams with various complex structures of phase and intensity in a colloidal suspension of gold nanoparticles with a plasmonic resonance near the laser wavelength (532nm). Studying optical vortices embedded in Gaussian beams, Bessel vortices and Bessel-cosine (necklace) beams, we gather evidence that while intense vortices turn into two-dimensional dark solitons, all structured wavepackets are able to guide a weak Gaussian probe of different wavelength (632.8 nm) along the dark core. The probe confinement also depends on the topological charge of the singular pump.
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8
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Yao F, Hong R, Zhang B, Pei Y, Hou C, Sun X. Electrically tunable polarization of random lasing from dye-doped nematic liquid crystals. OPTICS LETTERS 2020; 45:6118-6121. [PMID: 33186929 DOI: 10.1364/ol.402660] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/13/2020] [Accepted: 10/02/2020] [Indexed: 06/11/2023]
Abstract
Tunable polarizing direction of random lasing emission by an applied electric field which radiated from the lateral end face of homogeneously aligned, dye-doped nematic liquid crystal (NLC) cell was demonstrated for the first time, to the best of our knowledge. The lasing emission was partially polarized in the direction along the director of the NLC without the applied electric field. By tuning the applied electric field, the NLC director could be rotated to arbitrary direction from homogeneous to homeotropic alignment, resulting in the polarizing direction of lasing emission to any direction from parallel to perpendicular to the substrate surface in the end face.
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9
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Ming W, Chen F, Hu X, Zhang Z, Chang S, Chen R, Tian B, Zhang J. Synthesis and optical properties of 1-naphthol rhodamine for deep red laser dyes. Tetrahedron 2020. [DOI: 10.1016/j.tet.2020.131420] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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10
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Bera KP, Kamal S, Inamdar AI, Sainbileg B, Lin HI, Liao YM, Ghosh R, Chang TJ, Lee YG, Cheng-Fu H, Hsu YT, Hayashi M, Hung CH, Luo TT, Lu KL, Chen YF. Intrinsic Ultralow-Threshold Laser Action from Rationally Molecular Design of Metal-Organic Framework Materials. ACS APPLIED MATERIALS & INTERFACES 2020; 12:36485-36495. [PMID: 32678568 DOI: 10.1021/acsami.0c07890] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Metal-organic frameworks (MOFs) are superior for multiple applications including drug delivery, sensing, and gas storage because of their tunable physiochemical properties and fascinating architectures. Optoelectronic application of MOFs is difficult because of their porous geometry and conductivity issues. Recently, a few optoelectronic devices have been fabricated by a suitable design of integrating MOFs with other materials. However, demonstration of laser action arising from MOFs as intrinsic gain media still remains challenging, even though some studies endeavor on encapsulating luminescence organic laser dyes into the porous skeleton of MOFs to achieve laser action. Unfortunately, the aggregation of such unstable laser dyes causes photoluminescence quenching and energy loss, which limits their practical application. In this research, unprecedently, we demonstrated ultralow-threshold (∼13 nJ/cm2) MOF laser action by a judicious choice of metal nodes and organic linkers during synthesis of MOFs. Importantly, we also demonstrated that the white random lasing from the beautiful microflowers of organic linkers possesses a porous network, which is utilized to synthesize the MOFs. The highly luminescent broad-band organic linker 1,4-NDC, which itself exhibits a strong white random laser, is used not only to achieve the stimulated emission in MOFs but also to reduce the lasing threshold. Such white lasing has multiple applications from bioimaging to the recently developed versatile Li-Fi technology. In addition, we showed that the smooth facets of MOF microcrystals can show Fabry-Perot resonant cavities having a high quality factor of ∼103 with excellent photostability. Our unique discovery of stable, nontoxic, high-performance MOF laser action will open up a new route for the development of new optoelectronic devices.
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Affiliation(s)
- Krishna Prasad Bera
- Department of Physics, National Taiwan University, Taipei 10617, Taiwan
- Nano-Science and Technology Program, Taiwan International Graduate Program, Academia Sinica, Taipei 11529, Taiwan
| | - Saqib Kamal
- Institute of Chemistry, Academia Sinica, Taipei 115, Taiwan
- Molecular-Science and Technology Program,Taiwan International Graduate Program, Academia Sinica, Taipei 11529, Taiwan
- Department of Chemistry, National Tsing Hua University, Hsinchu 300, Taiwan
| | - Arif I Inamdar
- Sustainable Chemical Science and Technology, Taiwan International Graduate Program, Academia Sinica, Taipei 106, Taiwan and Department of Applied Chemistry, National Chiao Tung University, Hsinchu 300, Taiwan
- Institute of Chemistry, Academia Sinica, Taipei 115, Taiwan
| | - Batjargal Sainbileg
- Center for Condensed Matter Sciences, National Taiwan University, Taipei 10617, Taiwan
- Center of Atomic Initiative for New Materials, National Taiwan University, Taipei 10617, Taiwan
| | - Hung-I Lin
- Department of Physics, National Taiwan University, Taipei 10617, Taiwan
| | - Yu-Ming Liao
- Department of Physics, National Taiwan University, Taipei 10617, Taiwan
- Nano-Science and Technology Program, Taiwan International Graduate Program, Academia Sinica, Taipei 11529, Taiwan
| | - Rapti Ghosh
- Molecular-Science and Technology Program,Taiwan International Graduate Program, Academia Sinica, Taipei 11529, Taiwan
| | - Ting-Jia Chang
- Department of Physics, National Taiwan University, Taipei 10617, Taiwan
| | - Yen-Guang Lee
- Department of Physics, National Taiwan University, Taipei 10617, Taiwan
| | - Hou Cheng-Fu
- Department of Physics, National Taiwan University, Taipei 10617, Taiwan
- Nano-Science and Technology Program, Taiwan International Graduate Program, Academia Sinica, Taipei 11529, Taiwan
| | - Yun-Tzu Hsu
- Department of Physics, National Taiwan University, Taipei 10617, Taiwan
| | - Michitoshi Hayashi
- Center for Condensed Matter Sciences, National Taiwan University, Taipei 10617, Taiwan
- Center of Atomic Initiative for New Materials, National Taiwan University, Taipei 10617, Taiwan
| | | | - Tzuoo-Tsair Luo
- Department of Chemical Engineering and Biotechnology, National Taipei University of Technology, Taipei 106, Taiwan
| | - Kuang-Lieh Lu
- Institute of Chemistry, Academia Sinica, Taipei 115, Taiwan
| | - Yang-Fang Chen
- Department of Physics, National Taiwan University, Taipei 10617, Taiwan
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11
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Hu HW, Haider G, Liao YM, Roy PK, Lin HI, Lin SY, Chen YF. Ultralow Threshold Cavity-Free Laser Induced by Total Internal Reflection. ACS OMEGA 2020; 5:18551-18556. [PMID: 32775855 PMCID: PMC7407540 DOI: 10.1021/acsomega.9b04094] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/02/2019] [Accepted: 03/27/2020] [Indexed: 06/11/2023]
Abstract
Total internal reflection is one of the most important phenomena when a propagated wave strikes a medium boundary, which possesses a wide range of applications spanning from optical communication to a fluorescence microscope. It has also been widely used to demonstrate conventional laser actions with resonant cavities. Recently, cavity-free stimulated emission of radiation has attracted great attention in disordered media because of several exciting physical phenomena, ranging from Anderson localization of light to speckle-free imaging. However, unlike conventional laser systems, the total internal reflection has never been implemented in the study of laser actions derived from randomly distributed media. Herein, we demonstrate an ultra-low threshold cavity-free laser system using air bubbles as scattering centers in which the total internal reflection from the surface of air bubbles can greatly reduce the leakage of the scattered beam energy and then enhance light amplification within a coherent closed loop. Our approach provides an excellent alternative for the manipulation of optical energy flow to achieve ultra-low threshold cavity-free laser systems, which should be very useful for the development of high performance optoelectronic devices.
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Affiliation(s)
- Han-Wen Hu
- Department
of Physics, National Taiwan University, Taipei 10617, Taiwan
| | - Golam Haider
- Academy
of Sciences of the Czech Republic, J. Heyrovský
Institute of Physical Chemistry, Prague 8, Czechia
| | - Yu-Ming Liao
- Department
of Physics, National Taiwan University, Taipei 10617, Taiwan
| | - Pradip Kumar Roy
- Department
of Physics, National Taiwan University, Taipei 10617, Taiwan
| | - Hung-I. Lin
- Department
of Physics, National Taiwan University, Taipei 10617, Taiwan
| | - Shih-Yao Lin
- Department
of Physics, National Taiwan University, Taipei 10617, Taiwan
| | - Yang-Fang Chen
- Department
of Physics, National Taiwan University, Taipei 10617, Taiwan
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12
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Kwaśny M, Karpierz MA, Assanto G, Laudyn UA. Optothermal vortex-solitons in liquid crystals. OPTICS LETTERS 2020; 45:2451-2453. [PMID: 32287256 DOI: 10.1364/ol.388340] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/04/2020] [Accepted: 03/27/2020] [Indexed: 06/11/2023]
Abstract
We report on vortex-solitons generated in dye-doped nematic liquid crystals by a purely optothermal nonlocal nonlinearity. This response not only supports stable doughnut-shaped ordinary-wave beams with orbital angular momentum, but also provides self-confined solitary waves with excellent trajectory and profile stability over time. Using an interferometric technique, we also investigate the role of nonlocal nonlinearity in the non-illuminated axial region.
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13
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Laudyn UA, Kwaśny M, Karpierz MA, Assanto G. Vortex nematicons in planar cells. OPTICS EXPRESS 2020; 28:8282-8290. [PMID: 32225456 DOI: 10.1364/oe.386422] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/20/2019] [Accepted: 02/29/2020] [Indexed: 06/10/2023]
Abstract
We provide experimental evidence that stable vortex-solitons in nematic liquid crystals, termed vortex nematicons, can be generated in planar cells without any external biases, neither electric nor magnetic. We report on nonlinear vortices with extraordinary-wave beams in various undoped samples, pin-pointing how material nonlocality and birefringence aid their stable propagation. Finally, we also demonstrate confinement and waveguiding of an incoherent co-polarized probe signal by the nonlinear vortex.
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14
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Wang Z, Cao M, Shao G, Zhang Z, Yu H, Chen Y, Zhang Y, Li Y, Xu B, Wang Y, Yao J. Coherent Random Lasing in Colloidal Quantum Dot-Doped Polymer-Dispersed Liquid Crystal with Low Threshold and High Stability. J Phys Chem Lett 2020; 11:767-774. [PMID: 31934764 DOI: 10.1021/acs.jpclett.9b03409] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
High-concentration (2-10 wt %) ZnCdSeS/ZnS alloyed quantum dot-doped polymer-dispersed liquid crystals (QD-PDLCs) were prepared via ultraviolet (UV) curing. The QD-PDLC morphology and resonance characteristics of a coherent random laser were investigated. The doping concentration of the liquid crystal and quantum dots was varied to investigate its effect on the lasing threshold, line width, and stability with respect to the density and grain size of the liquid crystal droplets inside the PDLC structure. Furthermore, the QD-PDLC laser performance was influenced by the pump position and area because of spatial localization of the random resonators. Moreover, the QD-PDLC showed good long-term stability; after 15 days of laser excitation (3 h/day), the laser output was maintained at 92% of the original emission intensity. The random laser threshold was as low as 50 μJ/cm2 with the optimized preparation process, which suggested strong potential for applications in polymer random fiber lasers, sensors, and displays.
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Affiliation(s)
- Zhiwen Wang
- Faculty of Intelligent Manufacturing , Wuyi University , Jiangmen 529020 , China
| | - Mingxuan Cao
- Faculty of Intelligent Manufacturing , Wuyi University , Jiangmen 529020 , China
- Research Center for Polymer Engineering of Intelligent Manufacturing , Wuyi University , Jiangmen 529020 , China
| | - Genrong Shao
- Poly OptoElectronics Tech. Ltd , Jiangmen 529020 , China
| | - Zhikun Zhang
- Poly OptoElectronics Tech. Ltd , Jiangmen 529020 , China
| | - Huiwen Yu
- Faculty of Intelligent Manufacturing , Wuyi University , Jiangmen 529020 , China
- Research Center for Polymer Engineering of Intelligent Manufacturing , Wuyi University , Jiangmen 529020 , China
| | - Yeqing Chen
- School of Applied Physics and Materials , Wuyi University , Jiangmen 529020 , China
| | - Yating Zhang
- College of Precision Instruments and Optoelectronics Engineering , Tianjin University , Tianjin 300072 , China
| | - Yang Li
- Poly OptoElectronics Tech. Ltd , Jiangmen 529020 , China
| | - Baiping Xu
- Faculty of Intelligent Manufacturing , Wuyi University , Jiangmen 529020 , China
- Research Center for Polymer Engineering of Intelligent Manufacturing , Wuyi University , Jiangmen 529020 , China
| | - Ying Wang
- Faculty of Intelligent Manufacturing , Wuyi University , Jiangmen 529020 , China
| | - Jianquan Yao
- College of Precision Instruments and Optoelectronics Engineering , Tianjin University , Tianjin 300072 , China
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15
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Pump-Controlled Plasmonic Random Lasers from Dye-Doped Nematic Liquid Crystals with TiN Nanoparticles in Non-Oriented Cells. APPLIED SCIENCES-BASEL 2019. [DOI: 10.3390/app10010199] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Manipulation of the performance of the random lasers from dye-doped nematic liquid crystals with TiN nanoparticles in non-oriented cells is studied. The experimental results show that the introduction of TiN nanoparticles into dye-doped nematic liquid crystals significantly reduces the threshold of random lasing due to the localized surface plasmon resonance of TiN nanoparticles. The emission spectrum of random lasers can be controlled by the shape of the pump spot. The threshold of random lasers increases with the decrease of the length of pump stripe. In order to obtain the emission spectrum with fine discrete sharp peaks, the narrow pump stripe is more effective than the circular pump spot. When the pump area is more like a circle, the emission spectrum is more like an amplified spontaneous emission. The underlying mechanisms of these phenomena are discussed in detail. This study provides a promising platform for designing the high-quality and low-threshold random lasers which can be controlled by the shape of the pump spot.
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16
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Perumbilavil S, Kauranen M, Assanto G. Spatiospectral features of a soliton-assisted random laser in liquid crystals. OPTICS LETTERS 2019; 44:3574-3577. [PMID: 31305575 DOI: 10.1364/ol.44.003574] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/24/2019] [Accepted: 06/20/2019] [Indexed: 06/10/2023]
Abstract
We report on novel features of random lasers assisted by near-infrared spatial solitons in nematic liquid crystals. Specifically, we study the role of light-induced reorientational waveguides (nematicons) on the spatial and spectral distributions of the laser modes. We show that the spatially spiky character of the laser emission propagating backwards with respect to the pump tends to disappear in the forward direction, due to the soliton confinement of the generated light. Moreover, the spectral features associated with various random laser resonances appear to merge upon guided-wave propagation along the nematicon, making the nematicon-aided random laser a bidirectional device with distinct emission properties at the two opposite outputs.
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17
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Laudyn UA, Kwaśny M, Karpierz MA, Assanto G. Electro-optic quenching of nematicon fluctuations. OPTICS LETTERS 2019; 44:167-170. [PMID: 30645576 DOI: 10.1364/ol.44.000167] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/26/2018] [Accepted: 11/27/2018] [Indexed: 06/09/2023]
Abstract
Employing a low-frequency external electric field bias in nematic liquid crystals with negative dielectric anisotropy, we demonstrate that the trajectory fluctuations of reorientational spatial solitons can be substantially reduced, improving confinement and polarization purity of the output beams.
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18
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Laudyn UA, Piccardi A, Kwasny M, Klus B, Karpierz MA, Assanto G. Interplay of Thermo-Optic and Reorientational Responses in Nematicon Generation. MATERIALS 2018; 11:ma11101837. [PMID: 30261684 PMCID: PMC6212951 DOI: 10.3390/ma11101837] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/31/2018] [Revised: 09/21/2018] [Accepted: 09/25/2018] [Indexed: 11/16/2022]
Abstract
Employing several nematic liquid crystal mixtures, we investigate how the thermo-optic response of nonlinear birefringent soft-matter affects the propagation of light beams and the features of self-induced waveguides. We address the formation of optical spatial solitons and the control of their trajectories versus temperature, comparing the measurements with the expectations based on a simplified model, showing an excellent agreement. Moreover, in a guest⁻host mixture with an absorbing dye dopant, we study the competition between reorientational and thermal nonlinearities, demonstrating that the two processes can be adjusted independently in order to tune the soliton properties, i.e., trajectory and confinement strength. Our results are an important contribution to better comprehend the role played by material properties on linear and nonlinear beam propagation, as well as their exploitation for signal processing and addressing.
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Affiliation(s)
- Urszula A Laudyn
- Faculty of Physics, Warsaw University of Technology, PL-00662 Warsaw, Poland.
| | - Armando Piccardi
- NooEL-Nonlinear Optics and OptoElectronics Lab, University Roma Tre, I-00146 Rome, Italy.
| | - Michal Kwasny
- Faculty of Physics, Warsaw University of Technology, PL-00662 Warsaw, Poland.
| | - Bartlomiej Klus
- Faculty of Physics, Warsaw University of Technology, PL-00662 Warsaw, Poland.
| | - Miroslaw A Karpierz
- Faculty of Physics, Warsaw University of Technology, PL-00662 Warsaw, Poland.
| | - Gaetano Assanto
- NooEL-Nonlinear Optics and OptoElectronics Lab, University Roma Tre, I-00146 Rome, Italy.
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