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Masharin MA, Oskolkova T, Isik F, Volkan Demir H, Samusev AK, Makarov SV. Giant Ultrafast All-Optical Modulation Based on Exceptional Points in Exciton-Polariton Perovskite Metasurfaces. ACS NANO 2024; 18:3447-3455. [PMID: 38252695 DOI: 10.1021/acsnano.3c10636] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/24/2024]
Abstract
Ultrafast all-optical modulation with optically resonant nanostructures is an essential technology for high-speed signal processing on a compact optical chip. Key challenges that exist in this field are relatively low and slow modulations in the visible range as well as the use of expensive materials. Here we develop an ultrafast all-optical modulator based on MAPbBr3 perovskite metasurface supporting exciton-polariton states with exceptional points. The additional angular and spectral filtering of the modulated light transmitted through the designed metasurface allows us to achieve 2500% optical signal modulation with the shortest modulation time of 440 fs at the pump fluence of ∼40 μJ/cm2. Such a value of the modulation depth is record-high among the existing modulators in the visible range, while the main physical effect behind it is polariton condensation. Scalable and cheap metasurface fabrication via nanoimprint lithography along with the simplicity of perovskite synthesis and deposition make the developed approach promising for real-life applications.
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Affiliation(s)
- Mikhail A Masharin
- UNAM-Institute of Materials Science and Nanotechnology, National Nanotechnology Research Center, Department of Electrical and Electronics Engineering, Department of Physics, Bilkent University, Ankara 06800, Turkey
- Laboratory of Bionanophotonic, Institute of Bioengineering, École Polytechnique Fédérale de Lausanne (EPFL), Lausanne 1015, Switzerland
| | - Tatiana Oskolkova
- UNAM-Institute of Materials Science and Nanotechnology, National Nanotechnology Research Center, Department of Electrical and Electronics Engineering, Department of Physics, Bilkent University, Ankara 06800, Turkey
| | - Furkan Isik
- UNAM-Institute of Materials Science and Nanotechnology, National Nanotechnology Research Center, Department of Electrical and Electronics Engineering, Department of Physics, Bilkent University, Ankara 06800, Turkey
| | - Hilmi Volkan Demir
- UNAM-Institute of Materials Science and Nanotechnology, National Nanotechnology Research Center, Department of Electrical and Electronics Engineering, Department of Physics, Bilkent University, Ankara 06800, Turkey
- LUMINOUS! Center of Excellence for Semiconductor Lighting and Displays, School of Electrical and Electronic Engineering, School of Physical and Mathematical Sciences, School of Materials Science and Engineering, Nanyang Technological University, 639798, Singapore
| | - Anton K Samusev
- Experimentelle Physik 2, Technische Universität Dortmund, Dortmund 44227, Germany
| | - Sergey V Makarov
- Qingdao Innovation and Development Center, Harbin Engineering University, Qingdao, Shandong 266000, China
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2
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Wu J, Clementi M, Huang C, Ye F, Fu H, Lu L, Zhang S, Li Q, Brès CS. Thermo-optic epsilon-near-zero effects. Nat Commun 2024; 15:794. [PMID: 38278795 PMCID: PMC10817958 DOI: 10.1038/s41467-024-45054-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2023] [Accepted: 01/12/2024] [Indexed: 01/28/2024] Open
Abstract
Nonlinear epsilon-near-zero (ENZ) nanodevices featuring vanishing permittivity and CMOS-compatibility are attractive solutions for large-scale-integrated systems-on-chips. Such confined systems with unavoidable heat generation impose critical challenges for semiconductor-based ENZ performances. While their optical properties are temperature-sensitive, there is no systematic analysis on such crucial dependence. Here, we experimentally report the linear and nonlinear thermo-optic ENZ effects in indium tin oxide. We characterize its temperature-dependent optical properties with ENZ frequencies covering the telecommunication O-band, C-band, and 2-μm-band. Depending on the ENZ frequency, it exhibits an unprecedented 70-93-THz-broadband 660-955% enhancement over the conventional thermo-optic effect. The ENZ-induced fast-varying large group velocity dispersion up to 0.03-0.18 fs2nm-1 and its temperature dependence are also observed for the first time. Remarkably, the thermo-optic nonlinearity demonstrates a 1113-2866% enhancement, on par with its reported ENZ-enhanced Kerr nonlinearity. Our work provides references for packaged ENZ-enabled photonic integrated circuit designs, as well as a new platform for nonlinear photonic applications and emulations.
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Affiliation(s)
- Jiaye Wu
- École Polytechnique Fédérale de Lausanne (EPFL), Photonic Systems Laboratory (PHOSL), STI-IEM, Station 11, Lausanne, CH-1015, Switzerland.
| | - Marco Clementi
- École Polytechnique Fédérale de Lausanne (EPFL), Photonic Systems Laboratory (PHOSL), STI-IEM, Station 11, Lausanne, CH-1015, Switzerland
| | - Chenxingyu Huang
- School of Electronic and Computer Engineering, Peking University, Shenzhen, 518055, China
- Tsinghua Shenzhen International Graduate School, Tsinghua University, Shenzhen, 518055, China
| | - Feng Ye
- School of Electronic and Computer Engineering, Peking University, Shenzhen, 518055, China
| | - Hongyan Fu
- Tsinghua Shenzhen International Graduate School, Tsinghua University, Shenzhen, 518055, China
| | - Lei Lu
- School of Electronic and Computer Engineering, Peking University, Shenzhen, 518055, China
| | - Shengdong Zhang
- School of Electronic and Computer Engineering, Peking University, Shenzhen, 518055, China
| | - Qian Li
- School of Electronic and Computer Engineering, Peking University, Shenzhen, 518055, China.
| | - Camille-Sophie Brès
- École Polytechnique Fédérale de Lausanne (EPFL), Photonic Systems Laboratory (PHOSL), STI-IEM, Station 11, Lausanne, CH-1015, Switzerland.
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3
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Chang WJ, Sakotic Z, Ware A, Green AM, Roman BJ, Kim K, Truskett TM, Wasserman D, Milliron DJ. Wavelength Tunable Infrared Perfect Absorption in Plasmonic Nanocrystal Monolayers. ACS NANO 2024; 18:972-982. [PMID: 38117550 DOI: 10.1021/acsnano.3c09772] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/21/2023]
Abstract
The ability to efficiently absorb light in ultrathin (subwavelength) layers is essential for modern electro-optic devices, including detectors, sensors, and nonlinear modulators. Tailoring these ultrathin films' spectral, spatial, and polarimetric properties is highly desirable for many, if not all, of the above applications. Doing so, however, often requires costly lithographic techniques or exotic materials, limiting scalability. Here we propose, demonstrate, and analyze a mid-infrared absorber architecture leveraging monolayer films of nanoplasmonic colloidal tin-doped indium oxide nanocrystals (ITO NCs). We fabricate a series of ITO NC monolayer films using the liquid-air interface method; by synthetically varying the Sn dopant concentration in the NCs, we achieve spectrally selective perfect absorption tunable between wavelengths of two and five micrometers. We achieve monolayer thickness-controlled coupling strength tuning by varying NC size, allowing access to different coupling regimes. Furthermore, we synthesize a bilayer film that enables broadband absorption covering the entire midwave IR region (λ = 3-5 μm). We demonstrate a scalable platform, with perfect absorption in monolayer films only hundredths of a wavelength in thickness, enabling strong light-matter interaction, with potential applications for molecular detection and ultrafast nonlinear optical applications.
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Affiliation(s)
- Woo Je Chang
- McKetta Department of Chemical Engineering, University of Texas at Austin, Austin, Texas 78712, United States
| | - Zarko Sakotic
- Chandra Family Department of Electrical and Computer Engineering, University of Texas at Austin, Austin, Texas 78758, United States
| | - Alexander Ware
- Chandra Family Department of Electrical and Computer Engineering, University of Texas at Austin, Austin, Texas 78758, United States
| | - Allison M Green
- McKetta Department of Chemical Engineering, University of Texas at Austin, Austin, Texas 78712, United States
| | - Benjamin J Roman
- McKetta Department of Chemical Engineering, University of Texas at Austin, Austin, Texas 78712, United States
| | - Kihoon Kim
- McKetta Department of Chemical Engineering, University of Texas at Austin, Austin, Texas 78712, United States
| | - Thomas M Truskett
- McKetta Department of Chemical Engineering, University of Texas at Austin, Austin, Texas 78712, United States
- Department of Physics, University of Texas at Austin, Austin, Texas 78712, United States
| | - Daniel Wasserman
- Chandra Family Department of Electrical and Computer Engineering, University of Texas at Austin, Austin, Texas 78758, United States
| | - Delia J Milliron
- McKetta Department of Chemical Engineering, University of Texas at Austin, Austin, Texas 78712, United States
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Kim H, Kim G, Jeon YU, Lee W, Lee BH, Kim IS, Lee K, Kim SJ, Kim J. Perovskite Lanthanum-Doped Barium Stannate: A Refractory Near-Zero-Index Material for High-Temperature Energy Harvesting Systems. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2024; 11:e2302410. [PMID: 37997197 PMCID: PMC10787089 DOI: 10.1002/advs.202302410] [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: 04/16/2023] [Revised: 10/22/2023] [Indexed: 11/25/2023]
Abstract
The recent interests in bridging intriguing optical phenomena and thermal energy management has led to the demonstration of controlling thermal radiation with epsilon-near-zero (ENZ) and the related near-zero-index (NZI) optical media. In particular, the manipulation of thermal emission using phononic ENZ and NZI materials has shown promise in mid-infrared radiative cooling systems operating under low-temperature environments (below 100 °C). However, the absence of NZI materials capable of withstanding high temperatures has limited the spectral extension of these advanced technologies to the near-infrared (NIR) regime. Herein, a perovskite conducting oxide, lanthanum-doped barium stannate (La:BaSnO3 [LBSO]), as a refractory NZI material well suited for engineering NIR thermal emission is proposed. This work focuses on the experimental demonstration of superior high-temperature stability (of at least 1000 °C) of LBSO films in air and its durability under intense UV-pulsed laser irradiation below peak power of 9 MW cm-2 . Based on the low optical-loss in LBSO, a selective narrow-band thermal emission utilizing a metal-insulator-metal (MIM) Fabry-Pérot nanocavity consisting of LBSO films as metallic component is demonstrated. This study shows that LBSO is an ideal candidate as a refractory NZI component for thermal energy conversion operating at high temperatures in air and under strong light irradiations.
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Affiliation(s)
- Hyebi Kim
- Nanophotonics Research Center, Korea Institute of Science and Technology (KIST), Seoul, 02792, Republic of Korea
- School of Electrical Engineering, Korea University, Seoul, 02841, Republic of Korea
| | - Geunpil Kim
- Nanophotonics Research Center, Korea Institute of Science and Technology (KIST), Seoul, 02792, Republic of Korea
- School of Electrical Engineering, Korea University, Seoul, 02841, Republic of Korea
| | - Young-Uk Jeon
- Nanophotonics Research Center, Korea Institute of Science and Technology (KIST), Seoul, 02792, Republic of Korea
- School of Electrical Engineering, Korea University, Seoul, 02841, Republic of Korea
| | - Wonjun Lee
- Nanophotonics Research Center, Korea Institute of Science and Technology (KIST), Seoul, 02792, Republic of Korea
- School of Electrical Engineering, Korea University, Seoul, 02841, Republic of Korea
| | - Byeong-Hyeon Lee
- Advanced Analysis Center, Korea Institute of Science and Technology (KIST), Seoul, 02792, Republic of Korea
| | - In Soo Kim
- Nanophotonics Research Center, Korea Institute of Science and Technology (KIST), Seoul, 02792, Republic of Korea
- KIST-SKKU Carbon-Neutral Research Center, Sungkyunkwan University (SKKU), Suwon, 16419, Republic of Korea
| | - Kwanil Lee
- Nanophotonics Research Center, Korea Institute of Science and Technology (KIST), Seoul, 02792, Republic of Korea
| | - Soo Jin Kim
- School of Electrical Engineering, Korea University, Seoul, 02841, Republic of Korea
| | - Jongbum Kim
- Nanophotonics Research Center, Korea Institute of Science and Technology (KIST), Seoul, 02792, Republic of Korea
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Wang M, Jiang H, Ma H, Zhao C, Zhao Y, Wang Z, Xu X, Shao J. A corrugated epsilon-nearzero saturable absorber for a high-performance 1.3 μm solid-state bulk laser. NANOSCALE 2023; 15:17434-17442. [PMID: 37855687 DOI: 10.1039/d3nr04161a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/20/2023]
Abstract
Epsilon-near-zero (ENZ) materials with vanishing permittivity exhibit unprecedented optical nonlinearity within subwavelength propagation lengths in the ENZ region, making them promising photoelectric materials that have achieved exciting results in ultrafast pulse laser modulations. In this study, we fabricated a novel saturable absorber (SA) based on a corrugated indium tin oxide (CITO) film with a symmetrical geometry using a low-cost self-assembly process. The strong saturable absorption of the CITO film triggered by the ENZ effect at normal incidence was comparable to that of the planar indium tin oxide (ITO) film at an optimal 60° incidence (TM polarization) at 1340 nm. In addition, the strong nonlinear optical properties of the CITO film were not limited by the incident angle and polarization state of the pump laser over a wide range of 0-20°. Benefiting from the excellent saturable absorption of CITO-based SA at normal incidence, a Q-switching operation with CITO-based SA at 1.34 μm was achieved in a Nd:YVO4 solid-state laser system, obtaining pulses of a duration of 85.6 ns, which was one order of magnitude narrower than that of the planar ITO-based SA. This study presents a new strategy for developing high-performance ENZ-based SAs and ultrafast lasers.
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Affiliation(s)
- Mengxia Wang
- Laboratory of Thin Film Optics, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai 201800, China.
- Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing 100049, China
- Key Laboratory of Materials for High Power Laser, Chinese Academy of Sciences, Shanghai 201800, China
| | - Hang Jiang
- Laboratory of Thin Film Optics, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai 201800, China.
- Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing 100049, China
- Key Laboratory of Materials for High Power Laser, Chinese Academy of Sciences, Shanghai 201800, China
| | - Hao Ma
- Laboratory of Thin Film Optics, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai 201800, China.
- Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing 100049, China
- Key Laboratory of Materials for High Power Laser, Chinese Academy of Sciences, Shanghai 201800, China
| | - Chuanrui Zhao
- State Key Lab of Crystal Materials, Shandong University, Jinan, 250100, China.
| | - Yuanan Zhao
- Laboratory of Thin Film Optics, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai 201800, China.
- Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing 100049, China
- Key Laboratory of Materials for High Power Laser, Chinese Academy of Sciences, Shanghai 201800, China
| | - Zhengping Wang
- State Key Lab of Crystal Materials, Shandong University, Jinan, 250100, China.
| | - Xinguang Xu
- State Key Lab of Crystal Materials, Shandong University, Jinan, 250100, China.
| | - Jianda Shao
- Laboratory of Thin Film Optics, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai 201800, China.
- Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing 100049, China
- Key Laboratory of Materials for High Power Laser, Chinese Academy of Sciences, Shanghai 201800, China
- Hangzhou Institute for Advanced Study, University of Chinese Academy of Sciences, Hangzhou, 310024, China.
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6
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Zhang C, Zhang Y, Du H, Liu C. Enhancement and redshift of vortex harmonic radiation in epsilon-near-zero materials. OPTICS EXPRESS 2023; 31:7725-7733. [PMID: 36859897 DOI: 10.1364/oe.484941] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/04/2023] [Accepted: 02/06/2023] [Indexed: 06/18/2023]
Abstract
The harmonic radiation from a vortex laser field interacting with an epsilon-near-zero (ENZ) material is numerically investigated via solving the Maxwell-paradigmatic-Kerr equations. For a laser field of long duration, the harmonics up to the seventh-order can be generated with a low laser intensity (∼109 W/cm2). Moreover, the intensities of high order vortex harmonics at the ENZ frequency are higher than at other frequency points due to the ENZ field enhancement effects. Interestingly, for a laser field of short duration, the obvious frequency redshift occurs beyond enhancement in high order vortex harmonic radiation. The reason is that the strong change of the laser waveform propagating in the ENZ material and the non-constant field enhancement factor around the ENZ frequency. Because the topological number of harmonic radiation is linearly proportional to its harmonic order, the high order vortex harmonics with redshift still possess the exact harmonic orders indicated by the transverse electric field distribution of each harmonic.
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Jiang H, Zhao Y, Ma H, Wu Y, Chen M, Wang M, Zhang W, Peng Y, Leng Y, Cao Z, Shao J. Thickness-dependent loss-induced failure of an ideal ENZ-enhanced optical response in planar ultrathin transparent conducting oxide films. OPTICS EXPRESS 2023; 31:2208-2224. [PMID: 36785239 DOI: 10.1364/oe.479098] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/24/2022] [Accepted: 12/16/2022] [Indexed: 06/18/2023]
Abstract
Ultrathin planar transparent conducting oxide (TCO) films are commonly used to enhance the optical response of epsilon-near-zero (ENZ) devices; however, our results suggest that thickness-dependent loss renders them ineffective. Here, we investigated the thickness-dependent loss of indium tin oxide (ITO) films and their effect on the ENZ-enhanced optical responses of ITO and ITO/SiO2 multilayer stacks. The experimental and computational results show that the optical loss of ITO films increases from 0.47 to 0.70 as the thickness decreases from 235 to 52 nm, which results in a reduction of 60% and 45% in the maximum field enhancement factor of a 52-nm monolayer ITO and 4-layer ITO/SiO2 multilayer stack, respectively. The experimental results show that the ENZ-enhanced nonlinear absorption coefficient of the 52-nm single-layer ITO film is -1.6 × 103 cm GW-1, which is 81% lower than that of the 235-nm ITO film (-8.6 × 103 cm GW-1), indicating that the thickness-dependent loss makes the ultrathin TCO films unable to obtain greater nonlinear responses. In addition, the increased loss reduces the cascading Berreman transmission valley intensity of the 4-layer ITO/SiO2 multilayer stack, resulting in a 42% reduction in the ENZ-enhanced nonlinear absorption coefficient compared to the 235-nm ITO film and a faster hot electron relaxation time. Our results suggest that the thickness and loss trade-off is an intrinsic property of TCO films and that the low-loss ultrathin TCO films are the key to the robust design and fabrication of novel ENZ devices based on flat ultrathin TCO films.
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Huang J, Liu D, Chen L, Li N, Miao L, Zhao C. Broadband saturable absorption of indium tin oxide nanocrystals toward mid-infrared regime. OPTICS LETTERS 2022; 47:6413-6416. [PMID: 36538451 DOI: 10.1364/ol.478536] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/17/2022] [Accepted: 11/11/2022] [Indexed: 06/17/2023]
Abstract
We experimentally demonstrate the ultrabroadband optical nonlinearity of indium tin oxide nanocrystals (ITO NCs) in the mid-infrared regime. Especially, the ITO NCs show considerable saturation absorption behavior with large modulation depth covering the spectral range from 2-µm to 10-µm wavelength. We also demonstrate the application of the optical nonlinearity to successfully modulate the erbium-doped fluoride fiber laser to deliver a nanosecond pulse with a signal-to-noise ratio over 43 dB at 2.8-µm wavelength. The results provide a promising platform for the development of ITO-based broadband and robust optoelectronic devices toward the deep mid-infrared spectral range.
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Vatani S, Barahimi B, Moravvej-Farshi MK. All-optical AZO-based modulator topped with Si metasurfaces. Sci Rep 2022; 12:21490. [PMID: 36513754 DOI: 10.1038/s41598-022-25991-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2022] [Accepted: 12/07/2022] [Indexed: 12/14/2022] Open
Abstract
All-optical communication systems are under continuous development to address different core elements of inconvenience. Here, we numerically investigate an all-optical modulator, realizing a highly efficient modulation depth of 22 dB and a low insertion loss of 0.32 dB. The tunable optical element of the proposed modulator is a layer of Al-doped Zinc Oxide (AZO), also known as an epsilon-near-zero transparent conductive oxide. Sandwiching the AZO layer between a carefully designed distributed Bragg reflector and a dielectric metasurface-i.e., composed of a two-dimensional periodic array of cubic Si-provides a guided-mode resonance at the OFF state of the modulator, preventing the incident signal reflection at λ = 1310 nm. We demonstrate the required pump fluence for switching between the ON/OFF states of the designed modulator is about a few milli-Joules per cm2. The unique properties of the AZO layer, along with the engineered dielectric metasurface above it, change the reflection from 1 to 93%, helping design better experimental configurations for the next-generation all-optical communication systems.
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Affiliation(s)
- Sareh Vatani
- Nano Plasmo-Photonic Research Group, Faculty of Electrical and Computer Engineering, Tarbiat Modares University, Tehran, 1411713116, Iran
| | - Behdad Barahimi
- Nano Plasmo-Photonic Research Group, Faculty of Electrical and Computer Engineering, Tarbiat Modares University, Tehran, 1411713116, Iran
| | - Mohammad Kazem Moravvej-Farshi
- Nano Plasmo-Photonic Research Group, Faculty of Electrical and Computer Engineering, Tarbiat Modares University, Tehran, 1411713116, Iran.
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Shi W, Liu H, Wang Z. Gain-Assisted Giant Third-Order Nonlinearity of Epsilon-Near-Zero Multilayered Metamaterials. NANOMATERIALS (BASEL, SWITZERLAND) 2022; 12:3499. [PMID: 36234626 PMCID: PMC9565463 DOI: 10.3390/nano12193499] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/13/2022] [Revised: 09/27/2022] [Accepted: 10/01/2022] [Indexed: 06/16/2023]
Abstract
We investigate the third-order nonlinear optical properties of epsilon-near-zero (ENZ) Au/dye-doped fused silica multilayered metamaterials in the visible spectral range for TM incident by using nonlocal effective medium theory at different incidence angles. The nonlocal response affects the permittivity of anisotropic metamaterials when the thickness of the layer cannot be much smaller than the incident wavelength. By doping pump dye gain material within the dielectric layer to compensate for the metal loss, the imaginary part of the effective permittivity is reduced to 10-4, and the optical nonlinear refractive index and nonlinear absorption coefficient are enhanced. The real and imaginary parts of the permittivity are simultaneously minimized when the central emission wavelength of the gain material is close to the ENZ wavelength, and the nonlinear refraction coefficient reaches the order of 10-5 cm2/W, which is five orders of magnitude larger than that of the nonlinear response of the metamaterial without the gain medium. Our results demonstrate that a smaller imaginary part of the permittivity can be obtained by doping gain materials within the dielectric layer; it offers the promise of designing metamaterials with large nonlinearity at arbitrary wavelengths.
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Affiliation(s)
- Wenjuan Shi
- State Key Laboratory of Transient Optics and Photonics, Xi’an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi’an 710119, China
- University of Chinese Academy of Sciences, Beijing 100084, China
| | - Hongjun Liu
- State Key Laboratory of Transient Optics and Photonics, Xi’an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi’an 710119, China
- Collaborative Innovation Center of Extreme Optics, Shanxi University, Taiyuan 030006, China
| | - Zhaolu Wang
- State Key Laboratory of Transient Optics and Photonics, Xi’an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi’an 710119, China
- University of Chinese Academy of Sciences, Beijing 100084, China
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11
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Jiang H, Zhao Y, Ma H, Wu Y, Chen M, Wang M, Zhang W, Peng Y, Leng Y, Cao Z, Shao J. Broad-Band Ultrafast All-Optical Switching Based on Enhanced Nonlinear Absorption in Corrugated Indium Tin Oxide Films. ACS NANO 2022; 16:12878-12888. [PMID: 35905035 DOI: 10.1021/acsnano.2c05139] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Ultrafast all-optical switches based on epsilon-near-zero (ENZ)-enhanced nonlinear refraction in transparent conducting oxides have achieved exciting results in realizing large absolute modulations. However, broad-band, polarization-independent, and wide-angle ultrafast all-optical switches have been challenging to produce, due to the inherent narrow band, polarization-dependent, and angle-dependent characteristics of the ENZ effect. To this end, we propose an ultrafast all-optical switch based on the enhanced nonlinear absorption of corrugated indium tin oxide (ITO) thin films. Taking advantage of the perfect absorption and localized field enhancement of the ENZ and localized surface plasmon resonance modes, we significantly enhanced the nonlinear absorption of the corrugated ITO film in the 1450-1650 nm telecom band. The experimental results show that the nonlinear saturable absorption coefficient of the corrugated ITO film at 1450 nm was as high as -1.5 × 105 cm GW-1, enabling all-optical switching to obtain an extinction ratio of 14.32 dB and an ultrafast switching time of 350 fs at a pump fluence of 18.51 mJ cm-2. Furthermore, the all-optical switch achieved an extinction ratio of over 15 dB and an insertion loss of approximately 2.6 dB within the 200 nm absorption band and exhibited polarization-independent and wide-angle features. The ultrafast temporal response can be attributed to intraband transient bleaching of the corrugated ITO film. Our findings demonstrate that corrugated ENZ films can overcome the inherent narrow-band, polarization-dependent, and angle-dependent problems of natural ENZ materials without increasing the response time, making them a potential ENZ ultrafast all-optical switching material platform.
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Affiliation(s)
- Hang Jiang
- Laboratory of Thin Film Optics, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai 201800, People's Republic of China
- Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing 100049, People's Republic of China
- Key Laboratory of Materials for High Power Laser, Chinese Academy of Sciences, Shanghai 201800, People's Republic of China
| | - Yuanan Zhao
- Laboratory of Thin Film Optics, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai 201800, People's Republic of China
- Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing 100049, People's Republic of China
- Key Laboratory of Materials for High Power Laser, Chinese Academy of Sciences, Shanghai 201800, People's Republic of China
| | - Hao Ma
- Laboratory of Thin Film Optics, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai 201800, People's Republic of China
- Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing 100049, People's Republic of China
- Key Laboratory of Materials for High Power Laser, Chinese Academy of Sciences, Shanghai 201800, People's Republic of China
| | - Yi Wu
- Laboratory of Thin Film Optics, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai 201800, People's Republic of China
- Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing 100049, People's Republic of China
- Key Laboratory of Materials for High Power Laser, Chinese Academy of Sciences, Shanghai 201800, People's Republic of China
| | - Meiling Chen
- Laboratory of Thin Film Optics, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai 201800, People's Republic of China
- Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing 100049, People's Republic of China
- Key Laboratory of Materials for High Power Laser, Chinese Academy of Sciences, Shanghai 201800, People's Republic of China
| | - Mengxia Wang
- Laboratory of Thin Film Optics, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai 201800, People's Republic of China
- Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing 100049, People's Republic of China
- Key Laboratory of Materials for High Power Laser, Chinese Academy of Sciences, Shanghai 201800, People's Republic of China
| | - Weili Zhang
- Laboratory of Thin Film Optics, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai 201800, People's Republic of China
- Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing 100049, People's Republic of China
- Key Laboratory of Materials for High Power Laser, Chinese Academy of Sciences, Shanghai 201800, People's Republic of China
| | - Yujie Peng
- State Key Laboratory of High Field Laser Physics, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai 201800, People's Republic of China
| | - Yuxin Leng
- State Key Laboratory of High Field Laser Physics, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai 201800, People's Republic of China
| | - Zhaoliang Cao
- Jiangsu Key Laboratory of Micro and Nano Heat Fluid Flow Technology and Energy Application, School of Physical Science and Technology, Suzhou University of Science and Technology, Suzhou 215009, People's Republic of China
| | - Jianda Shao
- Laboratory of Thin Film Optics, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai 201800, People's Republic of China
- Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing 100049, People's Republic of China
- Key Laboratory of Materials for High Power Laser, Chinese Academy of Sciences, Shanghai 201800, People's Republic of China
- Hangzhou Institute for Advanced Study, University of Chinese Academy of Sciences, Hangzhou 310024, People's Republic of China
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12
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Zhu R, Qi Y, Meng J. Novel nanomaterials based saturable absorbers for passive mode locked fiber laser at 1.5 μm. NANOTECHNOLOGY 2022; 33:182002. [PMID: 35051916 DOI: 10.1088/1361-6528/ac4d59] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/13/2021] [Accepted: 01/20/2022] [Indexed: 06/14/2023]
Abstract
Compared with continuous wave lasers, ultrafast lasers have the advantages of ultra-short pulse width and ultra-high peak power, and have significant applications in optical communications, medical diagnostics, and precision machining. Saturable absorber (SA) technology is the most effective technique for the generation of ultra-fast lasers, which are based on artificial SAs and natural SAs. Among them, the semiconductor saturable absorber mirror has become the most commonly used form at present. Recently, basic research and application of nanomaterials such as carbon nanotubes (CNTs) and graphene have been developed rapidly. Researchers have found that nanomaterials exhibit extraordinary characteristics in ultrafast photonics, such as the low saturation intensity of CNTs, zero-band gap of graphene, and extremely high modulation depth of the topological insulator nano-films. Since graphene was first reported as an SA in 2009, many other nanomaterials have been successively explored, resulting in the rapid development of novel nanomaterial-based SAs. In this paper, we classified the nanomaterials used in SA mode-locking technology at 1.5μm and reviewed their research progress with a particular focus on nonlinear optical properties, integration strategies, and applications in the field of ultrafast photonics.
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Affiliation(s)
- Rui Zhu
- Center for Advanced Laser Technology, Hebei University of Technology, Tianjin 300401, People's Republic of China
- Hebei Key Laboratory of Advanced Laser Technology and Equipment, Tianjin 300401, People's Republic of China
- School of Electronic and Information Engineering, Hebei University of Technology, Tianjin 300401,People's Republic of China
| | - Yaoyao Qi
- Center for Advanced Laser Technology, Hebei University of Technology, Tianjin 300401, People's Republic of China
- Hebei Key Laboratory of Advanced Laser Technology and Equipment, Tianjin 300401, People's Republic of China
- School of Electronic and Information Engineering, Hebei University of Technology, Tianjin 300401,People's Republic of China
| | - Jianfei Meng
- Center for Advanced Laser Technology, Hebei University of Technology, Tianjin 300401, People's Republic of China
- Hebei Key Laboratory of Advanced Laser Technology and Equipment, Tianjin 300401, People's Republic of China
- School of Electronic and Information Engineering, Hebei University of Technology, Tianjin 300401,People's Republic of China
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13
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Indium Tin Oxide Nanowire Arrays as a Saturable Absorber for Mid-Infrared Er:Ca0.8Sr0.2F2 Laser. NANOMATERIALS 2022; 12:nano12030454. [PMID: 35159801 PMCID: PMC8840723 DOI: 10.3390/nano12030454] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/25/2021] [Revised: 01/25/2022] [Accepted: 01/26/2022] [Indexed: 02/04/2023]
Abstract
We demonstrated a passively Q-switched Er:Ca0.8Sr0.2F2 laser with indium tin oxide nanowire arrays as an optical modulator in the mid-infrared region. In the Q-switched regime, the maximum output power of 58 mW with a slope efficiency of 18.3% was acquired. Meanwhile, the minimum pulse duration and highest repetition rate of the stable pulse trains were 490 ns and 17.09 kHz, corresponding to single pulse energy of 3.4 μJ and peak power of 6.93 W, respectively. To the best of our knowledge it was the first time that indium tin oxide nanowire arrays were employed as a saturable absorber to make pulse lasers carried out at 2.8 μm. The experimental data show that indium tin oxide nanowire arrays can be employed as a competitive candidate for saturable absorber in the field of mid-infrared solid-state lasers.
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14
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Wu J, Liu X, Fu H, Chang KC, Zhang S, Fu HY, Li Q. Manipulation of epsilon-near-zero wavelength for the optimization of linear and nonlinear absorption by supercritical fluid. Sci Rep 2021; 11:15936. [PMID: 34354198 PMCID: PMC8342460 DOI: 10.1038/s41598-021-95513-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2021] [Accepted: 07/23/2021] [Indexed: 11/15/2022] Open
Abstract
We introduce supercritical fluid (SCF) technology to epsilon-near-zero (ENZ) photonics for the first time and experimentally demonstrate the manipulation of the ENZ wavelength for the enhancement of linear and nonlinear optical absorption in ENZ indium tin oxide (ITO) nanolayer. Inspired by the SCF's applications in repairing defects, reconnecting bonds, introducing dopants, and boosting the performance of microelectronic devices, here, this technique is used to exploit the influence of the electronic properties on optical characteristics. By reducing oxygen vacancies and electron scattering in the SCF oxidation process, the ENZ wavelength is shifted by 23.25 nm, the intrinsic loss is reduced by 20%, and the saturable absorption modulation depth is enhanced by > 30%. The proposed technique offers a time-saving low-temperature technique to optimize the linear and nonlinear absorption performance of plasmonics-based ENZ nanophotonic devices.
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Affiliation(s)
- Jiaye Wu
- School of Electronic and Computer Engineering, Peking University, Shenzhen, 518055, China
| | - Xuanyi Liu
- Tsinghua Shenzhen International Graduate School, Tsinghua University, Shenzhen, 518055, China
| | - Haishi Fu
- School of Electronic and Computer Engineering, Peking University, Shenzhen, 518055, China
| | - Kuan-Chang Chang
- School of Electronic and Computer Engineering, Peking University, Shenzhen, 518055, China
| | - Shengdong Zhang
- School of Electronic and Computer Engineering, Peking University, Shenzhen, 518055, China
| | - H Y Fu
- Tsinghua Shenzhen International Graduate School, Tsinghua University, Shenzhen, 518055, China
| | - Qian Li
- School of Electronic and Computer Engineering, Peking University, Shenzhen, 518055, China.
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15
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Xu Y, Hu H, Wu H, Xu C, Zhang H, Jin L, Zou Y, Ma X, Yin J. Enhancing Q-Switched Fiber Laser Performance Based on Reverse Saturable and Saturable Absorption Properties of CuCrO 2 Nanoparticle-Polyimide Films. ACS APPLIED MATERIALS & INTERFACES 2021; 13:21748-21755. [PMID: 33913316 DOI: 10.1021/acsami.1c02762] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
We demonstrate CuCrO2 (CCO) nanoparticle (NP)-polyimide (PI) composite film as a saturable absorber (SA) to regulate the output characteristics of passively Q-switched fiber laser at 1.55 μm. Based on the reverse saturable and saturable absorptions of the CCO NP-PI film, the passively Q-switched fiber laser expressed two stages with the increase of pump power for substantial performance enhancement. Reverse saturation absorption is observed to introduce appropriate cavity loss, which constructs effective pathways for promoting both the modulation depth and over threshold degree, as well as reducing the photon lifetime. In particular, our results realized the pulse duration and repetition rate compressing simultaneously for the first time. The second stage output laser exhibits a peak power of 1016 mW and a single pulse energy of 183 nJ, which are about 88 and 9 times higher than those of the first stage. Furthermore, the optical-optical conversion efficiency is up to 1270%. All of these can evidently demonstrate the importance of the appropriate cavity loss design for optimizing the Q-switched pulse laser output characteristics.
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Affiliation(s)
- Yingtian Xu
- State Key Laboratory of High Power Semiconductor Lasers, Changchun University of Science and Technology, Changchun 130022, China
| | - Hanfei Hu
- State Key Laboratory of High Power Semiconductor Lasers, Changchun University of Science and Technology, Changchun 130022, China
| | - Hongda Wu
- State Key Laboratory of High Power Semiconductor Lasers, Changchun University of Science and Technology, Changchun 130022, China
| | - Chongyang Xu
- State Key Laboratory of High Power Semiconductor Lasers, Changchun University of Science and Technology, Changchun 130022, China
| | - He Zhang
- State Key Laboratory of High Power Semiconductor Lasers, Changchun University of Science and Technology, Changchun 130022, China
| | - Liang Jin
- State Key Laboratory of High Power Semiconductor Lasers, Changchun University of Science and Technology, Changchun 130022, China
| | - Yonggang Zou
- State Key Laboratory of High Power Semiconductor Lasers, Changchun University of Science and Technology, Changchun 130022, China
| | - Xiaohui Ma
- State Key Laboratory of High Power Semiconductor Lasers, Changchun University of Science and Technology, Changchun 130022, China
| | - Jingzhi Yin
- State Key Laboratory on Integrated Optoelectronics, College of Electronic Science and Engineering, Jilin University, 2699 Qian-Jin Street, Changchun 130012, People's Republic of China
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16
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Bohn J, Luk TS, Tollerton C, Hutchings SW, Brener I, Horsley S, Barnes WL, Hendry E. All-optical switching of an epsilon-near-zero plasmon resonance in indium tin oxide. Nat Commun 2021; 12:1017. [PMID: 33589641 PMCID: PMC7884677 DOI: 10.1038/s41467-021-21332-y] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2020] [Accepted: 01/20/2021] [Indexed: 11/09/2022] Open
Abstract
Nonlinear optical devices and their implementation into modern nanophotonic architectures are constrained by their usually moderate nonlinear response. Recently, epsilon-near-zero (ENZ) materials have been found to have a strong optical nonlinearity, which can be enhanced through the use of cavities or nano-structuring. Here, we study the pump dependent properties of the plasmon resonance in the ENZ region in a thin layer of indium tin oxide (ITO). Exciting this mode using the Kretschmann-Raether configuration, we study reflection switching properties of a 60 nm layer close to the resonant plasmon frequency. We demonstrate a thermal switching mechanism, which results in a shift in the plasmon resonance frequency of 20 THz for a TM pump intensity of 70 GW cm-2. For degenerate pump and probe frequencies, we highlight an additional two-beam coupling contribution, not previously isolated in ENZ nonlinear optics studies, which leads to an overall pump induced change in reflection from 1% to 45%.
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Affiliation(s)
- Justus Bohn
- School of Physics, University of Exeter, Exeter, UK.
| | - Ting Shan Luk
- Sandia National Laboratories, Albuquerque, NM, USA.,Center for Integrated Nanotechnologies, Sandia National Laboratories, Albuquerque, NM, USA
| | | | | | - Igal Brener
- Sandia National Laboratories, Albuquerque, NM, USA.,Center for Integrated Nanotechnologies, Sandia National Laboratories, Albuquerque, NM, USA
| | | | | | - Euan Hendry
- School of Physics, University of Exeter, Exeter, UK
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17
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Zhang D, Cui H, Zhu C, Lv K, Zhang H, Liu X, Qiu J. Nanoscale Engineering of Optical nonlinearity Based on a Metal Nitride/Oxide Heterostructure. ACS APPLIED MATERIALS & INTERFACES 2021; 13:1253-1260. [PMID: 33356088 DOI: 10.1021/acsami.0c18431] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
The abilities to modulate linear and nonlinear optical response of materials in the nanoscale are of central importance in the design and fabrication of photonic devices for applications like optical modulators. Here, based on a simple transition metal oxide/nitride (TiO2/TiN) system, we show that it is possible to tune the optical properties by controlling the nanoscale architecture. Through controlled oxidation of the plasmonic TiN nanoparticle surfaces, we observe a continuous change of linear and nonlinear optical (NLO) properties with the increase of the thickness of the oxide layer in the TiN/TiO2 heterogeneous architecture. The NLO response is manifested by the strong saturable absorption with a structurally tunable negative NLO absorption coefficient. The variation in the NLO absorption coefficient by up to 7-fold can be connected to the relative change in the volume fraction of the metallic core and the dielectric shell. We demonstrate further that the optimized TiN-TiO2 heterostructures can be used to drive an optical switch for pulse laser generation in the 1.5 μm wavelength region. Our results delineate a topochemical process for optimization of the NLO properties of common plasmonic materials for photonic applications based on simple materials chemistry.
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Affiliation(s)
- Duoduo Zhang
- School of Materials Science and Engineering, Zhejiang University, Hangzhou 310027, China
| | - Hao Cui
- School of Materials Science and Engineering, Zhejiang University, Hangzhou 310027, China
| | - Chenyang Zhu
- School of Materials Science and Engineering, Zhejiang University, Hangzhou 310027, China
| | - Kefan Lv
- School of Materials Science and Engineering, Zhejiang University, Hangzhou 310027, China
| | - Haoran Zhang
- School of Materials Science and Engineering, Zhejiang University, Hangzhou 310027, China
| | - Xiaofeng Liu
- School of Materials Science and Engineering, Zhejiang University, Hangzhou 310027, China
| | - Jianrong Qiu
- College of Optical Science and Engineering, Zhejiang University, Hangzhou 310027, China
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18
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Sun Y, Li H, Hou R, Diao M, Liang Y, Huang Z, Humphrey MG, Zhang C. Realizing Saturable Absorption and Reverse Saturable Absorption in a PEDOT:PSS Film via Electrical Modulation. ACS APPLIED MATERIALS & INTERFACES 2020; 12:48982-48990. [PMID: 33074650 DOI: 10.1021/acsami.0c14447] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Electrical tuning of the nonlinear absorption of materials has promising application potential, while studies remain rare. In this work, we show that the third-order nonlinear absorption of poly(3,4-ethylenedioxythiophene) chemically doped with poly(styrene sulfonic acid) [PEDOT:PSS] can be effectively modulated by external voltage. The nonlinear absorption of the film can be varied between reverse saturable absorption (RSA) and saturable absorption (SA) via voltage control with laser excitation at 800 nm, and the corresponding nonlinear absorption coefficient can be tuned in the range -1606 ± 73 to 521 ± 9 cm GW-1. The doping level and energy structure of PEDOT are modulated with different voltages. The undoped film affords two-photon absorption and accordingly the RSA response. A moderately doped sample has two polaron levels, and Pauli blocking associated with these two polaron levels results in SA. The bipolaron level in heavily doped PEDOT leads to excited-state absorption and therefore RSA behavior. The approach reported here can be applied to other semiconductors and is a convenient, effective, and promising method for the electrical tuning of the optical nonlinearity.
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Affiliation(s)
- Yanhui Sun
- School of Chemical Science and Engineering, Tongji University, Shanghai 200092, PR China
| | - Hui Li
- School of Chemical Science and Engineering, Tongji University, Shanghai 200092, PR China
| | - Ruipeng Hou
- School of Chemical Science and Engineering, Tongji University, Shanghai 200092, PR China
| | - Mengjuan Diao
- School of Chemical Science and Engineering, Tongji University, Shanghai 200092, PR China
| | - Ying Liang
- School of Chemical Science and Engineering, Tongji University, Shanghai 200092, PR China
| | - Zhipeng Huang
- School of Chemical Science and Engineering, Tongji University, Shanghai 200092, PR China
| | - Mark G Humphrey
- Research School of Chemistry, Australian National University, Canberra, ACT 2601, Australia
| | - Chi Zhang
- School of Chemical Science and Engineering, Tongji University, Shanghai 200092, PR China
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19
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Dai J, Luo H, Moloney M, Qiu J. Adjustable Graphene/Polyolefin Elastomer Epsilon-near-Zero Metamaterials at Radiofrequency Range. ACS APPLIED MATERIALS & INTERFACES 2020; 12:22019-22028. [PMID: 32315530 DOI: 10.1021/acsami.0c02979] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
While epsilon-near-zero (ENZ) metamaterials have marvelously shown various application prospects, the way to construct intrinsic ENZ metamaterials and adjust their ENZ properties precisely is still uncovered. The realization of stable and broadband ENZ properties at the radiofrequency range is of great significance. Herein graphene/polyolefin elastomer (POE) intrinsic ENZ metamaterials are initially constructed via the nanohybrid process. The metamaterials possess excellent adjustable ENZ properties by adjusting the content and reduction methods of graphene. The permittivities maintain between -1 and 1 steadily with increasing graphene content, which is attributed to the moderated carrier concentration of the conductive networks in the nanohybrids. Besides, different reduction methods also have significant impacts on ENZ properties. The hydrazine hydrate reduction method increases the maximum ENZ frequency region to 126 MHz. Lorentz type resonance is reasonable for the positive-negative transition in the ENZ frequency regions. As a significant indicator of the emergence of ENZ property, the sudden peak of dielectric loss tangent is observed. This work offers novel routes to construct intrinsic ENZ metamaterials with excellent adjustability in both values of permittivity and ENZ frequency regions.
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Affiliation(s)
- Ji Dai
- School of Materials Science and Engineering, Tongji University, Shanghai 201804, PR China
| | - Hongchun Luo
- School of Materials Science and Engineering, Tongji University, Shanghai 201804, PR China
| | - Mark Moloney
- Department of Chemistry, University of Oxford, 12 Mansfield Road, Oxford OX1 3TA, England
| | - Jun Qiu
- School of Materials Science and Engineering, Tongji University, Shanghai 201804, PR China
- Key Laboratory of Advanced Civil Engineering Materials, Tongji University, Education of Ministry, Shanghai 201804, PR China
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20
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Feng X, Liu J, Yang W, Yu X, Jiang S, Ning T, Liu J. Broadband indium tin oxide nanowire arrays as saturable absorbers for solid-state lasers. OPTICS EXPRESS 2020; 28:1554-1560. [PMID: 32121863 DOI: 10.1364/oe.380903] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/22/2019] [Accepted: 01/01/2020] [Indexed: 06/10/2023]
Abstract
Indium Tin Oxide nanowire arrays (ITO-NWAs), as epsilon-near-zero (ENZ) materials, exhibit a fast response time and a low saturable absorption intensity, which make them promising photoelectric materials. In this study, ITO-NWAs were successfully fabricated using a chemical vapor deposition (CVD) method, and the saturable absorption properties of this material were characterized in the near-infrared region. Further, passively Q-switched all-solid-state lasers were realized at wavelengths of 1.0, 1.3, and 2.0 µm using the as-prepared saturable absorber (SA). To the best of our knowledge, we present the first application of ITO-NWAs in all-solid-state lasers. The results reveal that ITO-NWAs may be applied as an SA while developing Q-switched lasers and that they exhibit a broad application prospect as broadband saturable absorption materials.
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21
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Wu J, Malomed BA, Fu HY, Li Q. Self-interaction of ultrashort pulses in an epsilon-near-zero nonlinear material at the telecom wavelength. OPTICS EXPRESS 2019; 27:37298-37307. [PMID: 31878512 DOI: 10.1364/oe.27.037298] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/16/2019] [Accepted: 11/23/2019] [Indexed: 06/10/2023]
Abstract
Dynamics of femtosecond pulses with the telecom carrier wavelength is investigated numerically in a subwavelength layer of an indium tin oxide (ITO) epsilon-near-zero (ENZ) material with high dispersion and high nonlinearity. Due to the subwavelength thickness of the ITO ENZ material, and the fact that the pulse's propagation time is shorter than its temporal width, multiple reflections give rise to self-interaction in both spectral and temporal domains, especially at wavelengths longer than at the ENZ point, at which the reflections are significantly stronger. A larger absolute value of the pulse's chirp strongly affects the self-interaction by redistributing energy between wavelengths, while the sign of the chirp affects the interaction in the temporal domain. It is also found that, when two identical pulses are launched simultaneously from both ends, a subwavelength counterpart of a standing-wave state can be established. It shows robust energy localization in the middle of the sample, in terms of both the spectral and temporal intensity distributions.
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22
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Jin L, Wu H, Xu Y, Wang G, Wang X, Shi L, Zhang H, Li D, Ma X, Yin J. Emerging transparent conducting oxides material: 2-dimensional plasmonic Zn doped CuGaO 2 nanoplates for Q-switched fiber laser. OPTICS EXPRESS 2019; 27:25718-25730. [PMID: 31510439 DOI: 10.1364/oe.27.025718] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/27/2019] [Accepted: 07/19/2019] [Indexed: 06/10/2023]
Abstract
A passively Q-switched Er3+ doped fiber laser has been realized by using Zn doped hexagonal CuGaO2 (CGZO) nanoplates (NPs) as a saturable absorber (SA) for the first time. The CGZO NPs SA film exhibits strong saturable absorption property, meanwhile with a small nonsaturable loss of 5.179%, and the modulation depth is up to 40.821%. A stable passively Q-switched laser, which was centered at 1559.75 nm, was achieved, and the threshold was as low as 42 mW. With an increase of the pump power from 42mW to 361mW, the pulse duration decreases from 36 μs to 1.71 μs, and the maximum output power of 12.1 mW is achieved. Particularly, the optical-optical conversion efficiency of the Q-Switched laser based on CGZO NPs reached 3.76%. Due to whispering-gallery-mode (WGM) resonance in CGZO NPs, the nonlinear optical response of CGZO NPs has been enhancement. These findings demonstrate that CGZO NPs are promising SA for fabricating high-efficiency and low-threshold pulse lasers.
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23
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Miao R, Hu Y, Ouyang H, Tang Y, Zhang C, You J, Zheng X, Xu Z, Cheng X, Jiang T. A polarized nonlinear optical response in a topological insulator Bi 2Se 3-Au nanoantenna hybrid-structure for all-optical switching. NANOSCALE 2019; 11:14598-14606. [PMID: 31305823 DOI: 10.1039/c9nr02616a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Nonlinear plasmons are becoming an appealing and intriguing research area due to their remarkable light concentration and manipulation abilities. In this work, the nonlinear absorption (NLA) phenomena of polarized nanoantenna arrays coupled with the low dimensional topological insulator Bi2Se3 are studied at different excitation wavelengths. Our experimental results indicate that a significant enhancement in the linear absorption coefficient is achieved by localized surface plasmon (LSP) resonance, with enhancement factors that are 10- and 8-fold in magnitude for the cases of 800 nm (y polarization) and 970 nm (x polarization), respectively. Moreover, by polarization sensitive studies under 800 nm laser excitation, this new Bi2Se3-Au nanoantenna hybrid-structure exhibits adverse absorption responses of enhancement and suppression compared to pure Bi2Se3 film, providing excellent potential for applications in information converters. In particular, under 800 nm pump light (10 GW cm-2), the transmittance intensity of 450 nm or 1064 nm continuous wave (CW) probe light alters back and forth when the polarization direction changes by 90°. Thus, "ON" and "OFF" modes of this Bi2Se3-Au nanoantenna hybrid structure-based switch are achieved by using 450 nm and 1064 nm light, respectively, with a corresponding modulation depth of 3.4% and 21.9%, which can be applied in versatile photonic devices.
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Affiliation(s)
- Runlin Miao
- College of Advanced Interdisciplinary Studies, National University of Defense Technology, Changsha 410073, China.
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24
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Guo Q, Pan J, Li D, Shen Y, Han X, Gao J, Man B, Zhang H, Jiang S. Versatile Mode-Locked Operations in an Er-Doped Fiber Laser with a Film-Type Indium Tin Oxide Saturable Absorber. NANOMATERIALS 2019; 9:nano9050701. [PMID: 31060316 PMCID: PMC6567301 DOI: 10.3390/nano9050701] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/03/2019] [Revised: 04/29/2019] [Accepted: 04/30/2019] [Indexed: 12/12/2022]
Abstract
We demonstrate the generation of versatile mode-locked operations in an Er-doped fiber laser with an indium tin oxide (ITO) saturable absorber (SA). As an epsilon-near-zero material, ITO has been only used to fashion a mode-locked fiber laser as an ITO nanoparticle-polyvinyl alcohol SA. However, this type of SA cannot work at high power or ensure that the SA materials can be transmitted by the light. Thus, we covered the end face of a fiber with a uniform ITO film using the radio frequency magnetron sputtering technology to fabricate a novel ITO SA. Using this new type of SA, single-wavelength pulses, dual-wavelength pulses, and triple-wavelength multi-pulses were achieved easily. The pulse durations of these mode-locked operations were 1.67, 6.91, and 1 ns, respectively. At the dual-wavelength mode-locked state, the fiber laser could achieve an output power of 2.91 mW and a pulse energy of 1.48 nJ. This study reveals that such a proposed film-type ITO SA has excellent nonlinear absorption properties, which can promote the application of ITO film for ultrafast photonics.
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Affiliation(s)
- Quanxin Guo
- Collaborative Innovation Center of Light Manipulations and Applications in Universities of Shandong, Shandong Normal University, Jinan 250014, China.
| | - Jie Pan
- Collaborative Innovation Center of Light Manipulations and Applications in Universities of Shandong, Shandong Normal University, Jinan 250014, China.
| | - Dengwang Li
- Collaborative Innovation Center of Light Manipulations and Applications in Universities of Shandong, Shandong Normal University, Jinan 250014, China.
- Shandong Key Laboratory of Medical Physics and Image Processing and Shandong Provincial Engineering and Technical Center of Light Manipulations, School of Physics and Electronics, Shandong Normal University, Jinan 250358, China.
| | - Yiming Shen
- Collaborative Innovation Center of Light Manipulations and Applications in Universities of Shandong, Shandong Normal University, Jinan 250014, China.
| | - Xile Han
- Collaborative Innovation Center of Light Manipulations and Applications in Universities of Shandong, Shandong Normal University, Jinan 250014, China.
| | - Jinjuan Gao
- Collaborative Innovation Center of Light Manipulations and Applications in Universities of Shandong, Shandong Normal University, Jinan 250014, China.
| | - Baoyuan Man
- Collaborative Innovation Center of Light Manipulations and Applications in Universities of Shandong, Shandong Normal University, Jinan 250014, China.
| | - Huanian Zhang
- Collaborative Innovation Center of Light Manipulations and Applications in Universities of Shandong, Shandong Normal University, Jinan 250014, China.
- Shandong Provincial Key Laboratory of Optics and Photonic Device, Jinan 250014, China.
| | - Shouzhen Jiang
- Collaborative Innovation Center of Light Manipulations and Applications in Universities of Shandong, Shandong Normal University, Jinan 250014, China.
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25
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Hui Z, Xu W, Li X, Guo P, Zhang Y, Liu J. Cu 2S nanosheets for ultrashort pulse generation in the near-infrared region. NANOSCALE 2019; 11:6045-6051. [PMID: 30869727 DOI: 10.1039/c9nr00080a] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
2D metal chalcogenide materials have received enormous attention due to their extraordinary bio-chemical, electronic, magnetic, thermal and optical properties. Compared with the typical two-dimensional transition metal dichalcogenides (TMDs) and topological insulators, cuprous sulfide (Cu2S) has very different two-dimensional lattice structures, along with excellent electro-catalysis and high conductivity. However, the nonlinear optical properties of Cu2S have never been studied until now. Here, the nonlinear photonics characteristics of Cu2S and its application in ultrafast lasers have been systematically studied for the first time. Through optical deposition of Cu2S nanosheets on a tapered fiber, the nonlinear optical properties of Cu2S nanosheets are measured through the interaction with the evanescent field. The results indicate that superior nonlinear saturable absorption properties with a modulation depth of 0.51% are achieved. An erbium-doped fiber (EDF) laser is constructed to verify the performance of the Cu2S saturable absorber (SA). The results show that an output pulse with 8.06 MHz repetition rate, 1.04 ps pulse duration, 1530.4 nm central wavelength and 3.1 nm spectral width without an obvious Kelly sideband is obtained. Considering the diversity of the metal chalcogenide family, various engineering applications may be developed from the nonlinear saturable absorption characteristics of Cu2S, including optical fiber communication/sensing, precision optical metrology, material processing and nonlinear optics.
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Affiliation(s)
- Zhanqiang Hui
- Xi'an University of Posts and Telecommunications, Electronic Engineering Institute, Xi'an, Shaanxi 710121, PR China
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Luo H, Kang Z, Gao Y, Peng H, Li J, Qin G, Liu Y. Large aspect ratio gold nanorods (LAR-GNRs) for mid-infrared pulse generation with a tunable wavelength near 3 μm. OPTICS EXPRESS 2019; 27:4886-4896. [PMID: 30876098 DOI: 10.1364/oe.27.004886] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/25/2018] [Accepted: 01/14/2019] [Indexed: 06/09/2023]
Abstract
We report a tunable passively Q-switched fiber laser at the wavelengths near 3 μm, using large aspect ratio gold nanorods (LAR-GNRs) as a saturable absorber (SA) for the first time. The GNRs with a large average aspect ratio of up to ~20 were prepared using the seed-mediated growth method, which yielded a strong absorption band of 2.2-3 μm with a peak at ~2600 nm, stemming from longitudinal surface plasmon resonance (SPR). The corresponding nonlinear absorption was characterized using 2.87 μm ultrafast pulses, giving the modulation depth of 8.89%, saturation intensity of 14.9 MW/cm2, and nonsaturation loss of 39.9%. When introducing the material into a tunable Ho3+/Pr3+ codoped ZBLAN fiber laser as a SA, stable Q-switched pulses with a tunable wavelength within 2.83-2.88 μm were achieved. The largest output power of 30.8 mW, repetition rate of 78.12 kHz, and narrowest pulse width of 2.18 μs were simultaneously attained when tuned to ~2.865 μm at the pump power of 307.2 mW, while the largest pulse energy of 0.48 μJ was obtained at the longest tuning edge of 2.88 μm. Our work indicates that LAR-GNRs are a type of versatile broadband SA material available for the mid-infrared region.
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Guo Q, Qin Z, Wang Z, Weng YX, Liu X, Xie G, Qiu J. Broadly Tunable Plasmons in Doped Oxide Nanoparticles for Ultrafast and Broadband Mid-Infrared All-Optical Switching. ACS NANO 2018; 12:12770-12777. [PMID: 30495926 DOI: 10.1021/acsnano.8b07866] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Plasmons in conducting nanostructures offer the means to efficiently manipulate light at the nanoscale with subpicosecond speed in an all-optical operation fashion, thus allowing for construction of high performance all-optical signal-processing devices. Here, by exploiting the ultrafast nonlinear optical properties of broadly tunable mid-infrared (MIR) plasmons in solution-processed, degenerately doped oxide nanoparticles, we demonstrate ultrafast all-optical switching in the MIR region, which features subpicosecond response speed (with recovery time constant of <400 fs) as well as an ultrabroadband response spectral range (covering 3.0-5.0 μm). Furthermore, with the degenerately doped nanoparticles as Q-switch, pulsed fiber lasers covering 2.0-3.5 μm were constructed, of which a watt-level fiber laser at 3.0 μm band shows superior overall performance among previously reported passively Q-switched fiber lasers at the same band. Notably, the degenerately doped nanoparticles show great potential to work in the spectral range over 3.0 μm, which is beyond the accessibility of commercially available but expensive semiconducting saturable absorber mirror (SESAM). Our work demonstrates a versatile while cost-effective material solution to ultrafast photonics in the technologically important MIR region.
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Affiliation(s)
- Qiangbing Guo
- State Key Laboratory of Modern Optical Instrumentation, College of Optical Science and Engineering , Zhejiang University , Hangzhou 310027 , China
| | - Zhipeng Qin
- Key Laboratory for Laser Plasmas (Ministry of Education), Collaborative Innovation Center of IFSA (CICIFSA), School of Physics and Astronomy , Shanghai Jiao Tong University , Shanghai 200240 , China
| | - Zhuan Wang
- Beijing National Laboratory for Condensed Matter Physics, CAS Key Laboratory of Soft Matter Physics , Institute of Physics, Chinese Academy of Sciences , Beijing 100190 , China
| | - Yu-Xiang Weng
- Beijing National Laboratory for Condensed Matter Physics, CAS Key Laboratory of Soft Matter Physics , Institute of Physics, Chinese Academy of Sciences , Beijing 100190 , China
- School of Physical Sciences , University of Chinese Academy of Sciences , Beijing 100049 , China
| | - Xiaofeng Liu
- School of Materials Science and Engineering , Zhejiang University , Hangzhou 310027 , China
| | - Guoqiang Xie
- Key Laboratory for Laser Plasmas (Ministry of Education), Collaborative Innovation Center of IFSA (CICIFSA), School of Physics and Astronomy , Shanghai Jiao Tong University , Shanghai 200240 , China
| | - Jianrong Qiu
- State Key Laboratory of Modern Optical Instrumentation, College of Optical Science and Engineering , Zhejiang University , Hangzhou 310027 , China
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Lian J, Zhang D, Hong R, Qiu P, Lv T, Zhang D. Defect-Induced Tunable Permittivity of Epsilon-Near-Zero in Indium Tin Oxide Thin Films. NANOMATERIALS 2018; 8:nano8110922. [PMID: 30405091 PMCID: PMC6267609 DOI: 10.3390/nano8110922] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/18/2018] [Revised: 11/02/2018] [Accepted: 11/05/2018] [Indexed: 11/20/2022]
Abstract
Defect-induced tunable permittivity of Epsilon-Near-Zero (ENZ) in indium tin oxide (ITO) thin films via annealing at different temperatures with mixed gases (98% Ar, 2% O2) was reported. Red-shift of λENZ (Epsilon-Near-Zero wavelength) from 1422 nm to 1995 nm in wavelength was observed. The modulation of permittivity is dominated by the transformation of plasma oscillation frequency and carrier concentration depending on Drude model, which was produced by the formation of structural defects and the reduction of oxygen vacancy defects during annealing. The evolution of defects can be inferred by means of X-ray diffraction (XRD), atomic force microscopy (AFM), and Raman spectroscopy. The optical bandgaps (Eg) were investigated to explain the existence of defect states. And the formation of structure defects and the electric field enhancement were further verified by finite-difference time domain (FDTD) simulation.
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Affiliation(s)
- Jiqing Lian
- Engineering Research Center of Optical Instrument and System, Ministry of Education and Shanghai Key Lab of Modern Optical System, University of Shanghai for Science and Technology, Shanghai 200093, China.
| | - Dawei Zhang
- Engineering Research Center of Optical Instrument and System, Ministry of Education and Shanghai Key Lab of Modern Optical System, University of Shanghai for Science and Technology, Shanghai 200093, China.
| | - Ruijin Hong
- Engineering Research Center of Optical Instrument and System, Ministry of Education and Shanghai Key Lab of Modern Optical System, University of Shanghai for Science and Technology, Shanghai 200093, China.
| | - Peizhen Qiu
- Engineering Research Center of Optical Instrument and System, Ministry of Education and Shanghai Key Lab of Modern Optical System, University of Shanghai for Science and Technology, Shanghai 200093, China.
| | - Taiguo Lv
- Engineering Research Center of Optical Instrument and System, Ministry of Education and Shanghai Key Lab of Modern Optical System, University of Shanghai for Science and Technology, Shanghai 200093, China.
| | - Daohua Zhang
- School of Electrical and Electronic Engineering, Nanyang Technological University, Singapore 639798, Singapore.
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Diroll BT, Schramke KS, Guo P, Kortshagen UR, Schaller RD. Ultrafast Silicon Photonics with Visible to Mid-Infrared Pumping of Silicon Nanocrystals. NANO LETTERS 2017; 17:6409-6414. [PMID: 28892635 DOI: 10.1021/acs.nanolett.7b03393] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Dynamic optical control of infrared (IR) transparency and refractive index is achieved using boron-doped silicon nanocrystals excited with mid-IR optical pulses. Unlike previous silicon-based optical switches, large changes in transmittance are achieved without a fabricated structure by exploiting strong light coupling of the localized surface plasmon resonance (LSPR) produced from free holes of p-type silicon nanocrystals. The choice of optical excitation wavelength allows for selectivity between hole heating and carrier generation through intraband or interband photoexcitation, respectively. Mid-IR optical pumping heats the free holes of p-Si nanocrystals to effective temperatures greater than 3500 K. Increases of the hole effective mass at high effective hole temperatures lead to a subpicosecond change of the dielectric function, resulting in a redshift of the LSPR, modulating mid-IR transmission by as much as 27%, and increasing the index of refraction by more than 0.1 in the mid-IR. Low hole heat capacity dictates subpicosecond hole cooling, substantially faster than carrier recombination, and negligible heating of the Si lattice, permitting mid-IR optical switching at terahertz repetition frequencies. Further, the energetic distribution of holes at high effective temperatures partially reverses the Burstein-Moss effect, permitting the modulation of transmittance at telecommunications wavelengths. The results presented here show that doped silicon, particularly in micro- or nanostructures, is a promising dynamic metamaterial for ultrafast IR photonics.
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Affiliation(s)
- Benjamin T Diroll
- Center for Nanoscale Materials, Argonne National Laboratory , 9700 S. Cass Avenue, Lemont, Illinois 60349, United States
| | - Katelyn S Schramke
- Department of Mechanical Engineering, University of Minnesota , 111 Church Street SE, Minneapolis, Minnesota 55455, United States
| | - Peijun Guo
- Center for Nanoscale Materials, Argonne National Laboratory , 9700 S. Cass Avenue, Lemont, Illinois 60349, United States
| | - Uwe R Kortshagen
- Department of Mechanical Engineering, University of Minnesota , 111 Church Street SE, Minneapolis, Minnesota 55455, United States
| | - Richard D Schaller
- Center for Nanoscale Materials, Argonne National Laboratory , 9700 S. Cass Avenue, Lemont, Illinois 60349, United States
- Department of Chemistry, Northwestern University , 2145 Sheridan Road, Evanston, Illinois 60208, United States
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