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Yu K, Jiang Y, Chen Y, Hu X, Chang J, Hartland GV, Wang GP. Compressible viscoelasticity of cell membranes determined by gigahertz-frequency acoustic vibrations. PHOTOACOUSTICS 2023; 31:100494. [PMID: 37131996 PMCID: PMC10149280 DOI: 10.1016/j.pacs.2023.100494] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/20/2023] [Revised: 04/09/2023] [Accepted: 04/11/2023] [Indexed: 05/04/2023]
Abstract
Membrane viscosity is an important property of cell biology, which determines cellular function, development and disease progression. Various experimental and computational methods have been developed to investigate the mechanics of cells. However, there have been no experimental measurements of the membrane viscosity at high-frequencies in live cells. High frequency measurements are important because they can probe viscoelastic effects. Here, we investigate the membrane viscosity at gigahertz-frequencies through the damping of the acoustic vibrations of gold nanoplates. The experiments are modeled using a continuum mechanics theory which reveals that the membranes display viscoelasticity, with an estimated relaxation time of ca. 5.7 + 2.4 / - 2.7 ps. We further demonstrate that membrane viscoelasticity can be used to differentiate a cancerous cell line (the human glioblastoma cells LN-18) from a normal cell line (the mouse brain microvascular endothelial cells bEnd.3). The viscosity of cancerous cells LN-18 is lower than that of healthy cells bEnd.3 by a factor of three. The results indicate promising applications of characterizing membrane viscoelasticity at gigahertz-frequency in cell diagnosis.
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Affiliation(s)
- Kuai Yu
- State Key Laboratory of Radio Frequency Heterogeneous Integration, College of Electronics and Information Engineering, Shenzhen University, Shenzhen 518060, China
| | - Yiqi Jiang
- Institute of Microscale Optoelectronics, Shenzhen University, Shenzhen 518060, China
| | - Yungao Chen
- Institute of Microscale Optoelectronics, Shenzhen University, Shenzhen 518060, China
| | - Xiaoyan Hu
- Institute of Biomedicine and Biotechnology, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen 518055, China
| | - Junlei Chang
- Institute of Biomedicine and Biotechnology, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen 518055, China
| | - Gregory V. Hartland
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana 46556, USA
| | - Guo Ping Wang
- State Key Laboratory of Radio Frequency Heterogeneous Integration, College of Electronics and Information Engineering, Shenzhen University, Shenzhen 518060, China
- Corresponding author.
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2
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Uthe B, Sader JE, Pelton M. Optical measurement of the picosecond fluid mechanics in simple liquids generated by vibrating nanoparticles: a review. REPORTS ON PROGRESS IN PHYSICS. PHYSICAL SOCIETY (GREAT BRITAIN) 2022; 85:103001. [PMID: 36049471 DOI: 10.1088/1361-6633/ac8e82] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/18/2022] [Accepted: 09/01/2022] [Indexed: 06/15/2023]
Abstract
Standard continuum assumptions commonly used to describe the fluid mechanics of simple liquids have the potential to break down when considering flows at the nanometer scale. Two common assumptions for simple molecular liquids are that (1) they exhibit a Newtonian response, where the viscosity uniquely specifies the linear relationship between the stress and strain rate, and (2) the liquid moves in tandem with the solid at any solid-liquid interface, known as the no-slip condition. However, even simple molecular liquids can exhibit a non-Newtonian, viscoelastic response at the picosecond time scales that are characteristic of the motion of many nanoscale objects; this viscoelasticity arises because these time scales can be comparable to those of molecular relaxation in the liquid. In addition, even liquids that wet solid surfaces can exhibit nanometer-scale slip at those surfaces. It has recently become possible to interrogate the viscoelastic response of simple liquids and associated nanoscale slip using optical measurements of the mechanical vibrations of metal nanoparticles. Plasmon resonances in metal nanoparticles provide strong optical signals that can be accessed by several spectroscopies, most notably ultrafast transient-absorption spectroscopy. These spectroscopies have been used to measure the frequency and damping rate of acoustic oscillations in the nanoparticles, providing quantitative information about mechanical coupling and exchange of mechanical energy between the solid particle and its surrounding liquid. This information, in turn, has been used to elucidate the rheology of viscoelastic simple liquids at the nanoscale in terms of their constitutive relations, taking into account separate viscoelastic responses for both shear and compressible flows. The nanoparticle vibrations have also been used to provide quantitative measurements of slip lengths on the single-nanometer scale. Viscoelasticity has been shown to amplify nanoscale slip, illustrating the interplay between different aspects of the unconventional fluid dynamics of simple liquids at nanometer length scales and picosecond time scales.
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Affiliation(s)
- Brian Uthe
- Department of Physics, UMBC (University of Maryland, Baltimore County), Baltimore, MD 21250, United States of America
| | - John E Sader
- School of Mathematics and Statistics, The University of Melbourne, Victoria 3010, Australia
| | - Matthew Pelton
- Department of Physics, UMBC (University of Maryland, Baltimore County), Baltimore, MD 21250, United States of America
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Ng RC, El Sachat A, Cespedes F, Poblet M, Madiot G, Jaramillo-Fernandez J, Florez O, Xiao P, Sledzinska M, Sotomayor-Torres CM, Chavez-Angel E. Excitation and detection of acoustic phonons in nanoscale systems. NANOSCALE 2022; 14:13428-13451. [PMID: 36082529 PMCID: PMC9520674 DOI: 10.1039/d2nr04100f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/25/2022] [Accepted: 08/15/2022] [Indexed: 06/15/2023]
Abstract
Phonons play a key role in the physical properties of materials, and have long been a topic of study in physics. While the effects of phonons had historically been considered to be a hindrance, modern research has shown that phonons can be exploited due to their ability to couple to other excitations and consequently affect the thermal, dielectric, and electronic properties of solid state systems, greatly motivating the engineering of phononic structures. Advances in nanofabrication have allowed for structuring and phonon confinement even down to the nanoscale, drastically changing material properties. Despite developments in fabricating such nanoscale devices, the proper manipulation and characterization of phonons continues to be challenging. However, a fundamental understanding of these processes could enable the realization of key applications in diverse fields such as topological phononics, information technologies, sensing, and quantum electrodynamics, especially when integrated with existing electronic and photonic devices. Here, we highlight seven of the available methods for the excitation and detection of acoustic phonons and vibrations in solid materials, as well as advantages, disadvantages, and additional considerations related to their application. We then provide perspectives towards open challenges in nanophononics and how the additional understanding granted by these techniques could serve to enable the next generation of phononic technological applications.
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Affiliation(s)
- Ryan C Ng
- Catalan Institute of Nanoscience and Nanotechnology (ICN2), CSIC and BIST, Campus UAB, Bellaterra, 08193 Barcelona, Spain.
| | | | - Francisco Cespedes
- Catalan Institute of Nanoscience and Nanotechnology (ICN2), CSIC and BIST, Campus UAB, Bellaterra, 08193 Barcelona, Spain.
- Departamento de Física, Universidad Autónoma de Barcelona, Bellaterra, 08193 Barcelona, Spain
| | - Martin Poblet
- Catalan Institute of Nanoscience and Nanotechnology (ICN2), CSIC and BIST, Campus UAB, Bellaterra, 08193 Barcelona, Spain.
| | - Guilhem Madiot
- Catalan Institute of Nanoscience and Nanotechnology (ICN2), CSIC and BIST, Campus UAB, Bellaterra, 08193 Barcelona, Spain.
| | - Juliana Jaramillo-Fernandez
- Catalan Institute of Nanoscience and Nanotechnology (ICN2), CSIC and BIST, Campus UAB, Bellaterra, 08193 Barcelona, Spain.
| | - Omar Florez
- Catalan Institute of Nanoscience and Nanotechnology (ICN2), CSIC and BIST, Campus UAB, Bellaterra, 08193 Barcelona, Spain.
- Departamento de Física, Universidad Autónoma de Barcelona, Bellaterra, 08193 Barcelona, Spain
| | - Peng Xiao
- Catalan Institute of Nanoscience and Nanotechnology (ICN2), CSIC and BIST, Campus UAB, Bellaterra, 08193 Barcelona, Spain.
- Departamento de Física, Universidad Autónoma de Barcelona, Bellaterra, 08193 Barcelona, Spain
| | - Marianna Sledzinska
- Catalan Institute of Nanoscience and Nanotechnology (ICN2), CSIC and BIST, Campus UAB, Bellaterra, 08193 Barcelona, Spain.
| | - Clivia M Sotomayor-Torres
- Catalan Institute of Nanoscience and Nanotechnology (ICN2), CSIC and BIST, Campus UAB, Bellaterra, 08193 Barcelona, Spain.
- ICREA, Passeig Lluis Companys 23, 08010 Barcelona, Spain
| | - Emigdio Chavez-Angel
- Catalan Institute of Nanoscience and Nanotechnology (ICN2), CSIC and BIST, Campus UAB, Bellaterra, 08193 Barcelona, Spain.
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Wang J, Li M, Jiang Y, Yu K, Hartland GV, Wang GP. Polymer dependent acoustic mode coupling and Hooke's law spring constants in stacked gold nanoplates. J Chem Phys 2021; 155:144701. [PMID: 34654293 DOI: 10.1063/5.0066661] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Metal nanoparticles are excellent acoustic resonators and their vibrational spectroscopy has been widely investigated. However, the coupling between vibrational modes of different nanoparticles is less explored. For example, how the intervening medium affects the coupling strength is not known. Here, we investigate how different polymers affect coupling in Au nanoplate-polymer-Au nanoplate sandwich structures. The coupling between the breathing modes of the Au nanoplates was measured using single-particle pump-probe spectroscopy, and the polymer dependent coupling strength was determined experimentally. Analysis of the acoustic mode coupling gives the effective spring constant for the polymers. A relative motion mode was also observed for the stacked Au nanoplates. The frequency of this mode is strongly correlated with the coupling constant for the breathing modes. The breathing mode coupling and relative motion mode were analyzed using a coupled oscillator model. This model shows that both these effects can be described using the same spring constant for the polymer. Finally, we present a new type of mass balance using the strongly coupled resonators. We show that the resonators have a mass detection limit of a few femtograms. We envision that further understanding of the vibrational coupling in acoustic resonators will improve the coupling strength and expand their potential applications.
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Affiliation(s)
- Junzhong Wang
- Institute of Microscale Optoelectronics, Shenzhen University, Shenzhen 518060, China
| | - Mengying Li
- Institute of Microscale Optoelectronics, Shenzhen University, Shenzhen 518060, China
| | - Yiqi Jiang
- Institute of Microscale Optoelectronics, Shenzhen University, Shenzhen 518060, China
| | - Kuai Yu
- Institute of Microscale Optoelectronics, Shenzhen University, Shenzhen 518060, China
| | - Gregory V Hartland
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana 46556, USA
| | - Guo Ping Wang
- Institute of Microscale Optoelectronics, Shenzhen University, Shenzhen 518060, China
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Uthe B, Collis JF, Madadi M, Sader JE, Pelton M. Highly Spherical Nanoparticles Probe Gigahertz Viscoelastic Flows of Simple Liquids Without the No-Slip Condition. J Phys Chem Lett 2021; 12:4440-4446. [PMID: 33955224 DOI: 10.1021/acs.jpclett.1c01013] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Simple liquids are conventionally described by Newtonian fluid mechanics, based on the assumption that relaxation processes in the flow occur much faster than the rate at which the fluid is driven. Nanoscale solids, however, have characteristic mechanical response times on the picosecond scale, which are comparable to mechanical relaxation times in simple liquids; as a result, viscoelastic effects in the liquid must be considered. These effects have been observed using time-resolved optical measurements of vibrating nanoparticles, but interpretation has often been complicated by finite velocity slip at the liquid-solid interface. Here, we use highly spherical gold nanoparticles to drive flows that are theoretically modeled without the use of the no-slip boundary condition at the particle surface. We obtain excellent agreement with this analytical theory that considers both the compression and shear relaxation properties of the liquid.
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Affiliation(s)
- Brian Uthe
- Department of Physics, UMBC (University of Maryland, Baltimore County), Baltimore, Maryland 21250, United States
| | - Jesse F Collis
- ARC Centre of Excellence in Exciton Science, School of Mathematics and Statistics, The University of Melbourne, Melbourne, Victoria 3010, Australia
| | - Mahyar Madadi
- ARC Centre of Excellence in Exciton Science, School of Mathematics and Statistics, The University of Melbourne, Melbourne, Victoria 3010, Australia
| | - John E Sader
- ARC Centre of Excellence in Exciton Science, School of Mathematics and Statistics, The University of Melbourne, Melbourne, Victoria 3010, Australia
| | - Matthew Pelton
- Department of Physics, UMBC (University of Maryland, Baltimore County), Baltimore, Maryland 21250, United States
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Chakraborty D, Uthe B, Malachosky EW, Pelton M, Sader JE. Viscoelasticity Enhances Nanometer-Scale Slip in Gigahertz-Frequency Liquid Flows. J Phys Chem Lett 2021; 12:3449-3455. [PMID: 33789041 DOI: 10.1021/acs.jpclett.1c00600] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
The interaction between flowing liquids and solid surfaces underpins many physical phenomena and technologies, such as the ability of an airfoil to generate lift and the mixing of liquids for industrial applications. These phenomena are often described using the Navier-Stokes equations and the no-slip boundary condition: the assumption that the liquid immediately adjacent to a solid surface does not move relative to the surface. Herein, we observe violation of the no-slip condition with strong enhancement of slip due to intrinsic viscoelasticity of the bulk liquid. This is achieved by measuring the 20 GHz acoustic vibrations of gold nanoparticles in glycerol/water mixtures, for which the underlying physics is explored using rigorous, theoretical models. The reported enhancement of slip revises current understanding of ultrafast liquid flows, with implications for technologies ranging from membrane filtration to nanofluidic devices and biomolecular sensing.
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Affiliation(s)
- Debadi Chakraborty
- ARC Centre of Excellence in Exciton Science, School of Mathematics and Statistics, The University of Melbourne, Victoria 3010, Australia
| | - Brian Uthe
- Department of Physics, UMBC (University of Maryland, Baltimore County), Baltimore, Maryland 21250, United States
| | - Edward W Malachosky
- James Franck Institute, University of Chicago, Chicago, Illinois 60637, United States
| | - Matthew Pelton
- Department of Physics, UMBC (University of Maryland, Baltimore County), Baltimore, Maryland 21250, United States
| | - John E Sader
- ARC Centre of Excellence in Exciton Science, School of Mathematics and Statistics, The University of Melbourne, Victoria 3010, Australia
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Yu K, Yang Y, Wang J, Hartland GV, Wang GP. Nanoparticle-Fluid Interactions at Ultrahigh Acoustic Vibration Frequencies Studied by Femtosecond Time-Resolved Microscopy. ACS NANO 2021; 15:1833-1840. [PMID: 33448792 DOI: 10.1021/acsnano.0c09840] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Liquid viscous and viscoelastic properties are very important parameters in determining rheological phenomena. Mechanical resonators with extremely high vibrational frequencies interacting with simple liquids present a wide range of applications from mass sensing to biomechanics. However, a lack of understanding of fluid viscoelasticity greatly hinders the utilization of mechanical resonators. In this paper, the high frequency acoustic vibrations of Au nanoplates with large quality factors were used to probe fluid properties (water, glycerol, and their mixtures) through time-resolved pump-probe microscopy experiments. For water, viscous damping was clearly observed, where an inviscid effect was only detected previously. Adding glycerol to the water increases the fluid viscosity and leads to a bulk viscoelastic response in the system. The experimental results are in excellent agreement with a continuum mechanics model for the damping of nanoplate breathing modes in liquids, confirming the experimental observation of viscoelastic effects. In addition to the breathing modes of the nanoplates, Brillouin oscillations are observed in the experiments. Analysis of the frequency of the Brillouin oscillations also shows the presence of viscoelastic effects in the high-viscosity solvents. The detection and analysis of viscous damping in liquids is important not only for understanding the energy dissipation mechanisms and providing the mechanical relaxation times of the liquids but also for developing applications of nanomechanical resonators for fluid environments.
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Affiliation(s)
- Kuai Yu
- Institute of Microscale Optoelectronics, Shenzhen University, Shenzhen 518060, China
| | - Yang Yang
- Institute of Microscale Optoelectronics, Shenzhen University, Shenzhen 518060, China
| | - Junzhong Wang
- Institute of Microscale Optoelectronics, Shenzhen University, Shenzhen 518060, China
| | - Gregory V Hartland
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana 46556, United States
| | - Guo Ping Wang
- Institute of Microscale Optoelectronics, Shenzhen University, Shenzhen 518060, China
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8
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Zhu Y, Cheng JX. Transient absorption microscopy: Technological innovations and applications in materials science and life science. J Chem Phys 2020; 152:020901. [PMID: 31941290 PMCID: PMC7195865 DOI: 10.1063/1.5129123] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2019] [Accepted: 12/15/2019] [Indexed: 01/08/2023] Open
Abstract
Transient absorption (TA) spectroscopy has been extensively used in the study of excited state dynamics of various materials and molecules. The transition from TA spectroscopy to TA microscopy, which enables the space-resolved measurement of TA, is opening new investigations toward a more complete picture of excited state dynamics in functional materials, as well as the mapping of crucial biopigments for precision diagnosis. Here, we review the recent instrumental advancement that is pushing the limit of spatial resolution, detection sensitivity, and imaging speed. We further highlight the emerging application in materials science and life science.
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Affiliation(s)
- Yifan Zhu
- Department of Chemistry, Boston University, Boston, Massachusetts 02215, USA
| | - Ji-Xin Cheng
- Department of Chemistry, Boston University, Boston, Massachusetts 02215, USA
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Devkota T, Yu K, Hartland GV. Mass loading effects in the acoustic vibrations of gold nanoplates. NANOSCALE 2019; 11:16208-16213. [PMID: 31453600 DOI: 10.1039/c9nr05940g] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
The breathing modes of single suspended gold nanoplates have been examined by transient absorption microscopy. These vibrational modes show very high quality factors which means that their frequencies can be accurately measured. Measurements performed before and after removing the organic layer that coats the as synthesized nanoplates show significant increases in frequency, which are consistent with removal of a few nm of organic material from the nanoplate surface. Experiments were also performed after depositing polymer beads on the sample. These measurements show a decrease in frequency in the region of the beads. This implies that adding a localized mass to the nanoplate hybridizes the vibrational normal modes, creating a new breathing mode which has a maximum amplitude at the bead. The nanoplate resonators have a mass sensing detection limit of ca. 10 attograms, which is comparable to the best results that have been achieved with plasmonic nanoparticles.
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Affiliation(s)
- Tuphan Devkota
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, IN 46556, USA.
| | - Kuai Yu
- College of Electronic Science and Technology, Shenzhen University, Shenzhen, 518060, P. R. China
| | - Gregory V Hartland
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, IN 46556, USA.
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Devkota T, Brown BS, Beane G, Yu K, Hartland GV. Making waves: Radiation damping in metallic nanostructures. J Chem Phys 2019; 151:080901. [PMID: 31470703 DOI: 10.1063/1.5117230] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
Metal nanostructures display several types of resonances. In the visible and near-IR spectral regions, there are localized surface plasmon resonances (LSPRs) that involve the coherent oscillation of the conduction electrons. Extended metal nanostructures, such as nanowires or nanoplates, also exhibit propagating surface plasmon polaritons (PSPPs), which are motions of the electrons at the surface of the structure that have a well-defined momentum. In addition, the vibrational normal modes of metal nanostructures give rise to low frequency resonances in the gigahertz to terahertz range. These different types of motions/resonances suffer energy losses from internal effects and from interactions with the environment. The goal of this perspective is to describe the part of the energy relaxation process due to the environment. Even though the plasmon resonances and acoustic vibrational modes arise from very different physics, it turns out that environmental damping is dominated by radiation of waves. The way the rates for radiation damping depend on the size of the nanostructure and the properties of the environment will be discussed for the different processes. For example, it is well known that for LSPRs, the rate of radiation damping increases with particle size. However, the radiation damping rate decreases with increasing dimensions for PSPPs and for the acoustic vibrational modes.
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Affiliation(s)
- Tuphan Devkota
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana 46556, USA
| | - Brendan S Brown
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana 46556, USA
| | - Gary Beane
- ARC Center of Excellence in Future Low-Energy Electronic Technologies, Monash University, Clayton, VIC 3800, Australia
| | - Kuai Yu
- College of Electronic Science and Technology, Shenzhen University, Shenzhen 518060, People's Republic of China
| | - Gregory V Hartland
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana 46556, USA
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Wang J, Yu K, Yang Y, Hartland GV, Sader JE, Wang GP. Strong vibrational coupling in room temperature plasmonic resonators. Nat Commun 2019; 10:1527. [PMID: 30948721 PMCID: PMC6449381 DOI: 10.1038/s41467-019-09594-z] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2019] [Accepted: 03/18/2019] [Indexed: 12/22/2022] Open
Abstract
Strong vibrational coupling has been realized in a variety of mechanical systems. However, there have been no experimental observations of strong coupling of the acoustic modes of plasmonic nanostructures, due to rapid energy dissipation in these systems. Here we realized strong vibrational coupling in ultra-high frequency plasmonic nanoresonators by increasing the vibrational quality factors by an order of magnitude. We achieved the highest frequency quality factor products of f × Q = 1.0 × 1013 Hz for the fundamental mechanical modes, which exceeds the value of 0.6 × 1013 Hz required for ground state cooling. Avoided crossing was observed between vibrational modes of two plasmonic nanoresonators with a coupling rate of g = 7.5 ± 1.2 GHz, an order of magnitude larger than the dissipation rates. The intermodal strong coupling was consistent with theoretical calculations using a coupled oscillator model. Our results enabled a platform for future observation and control of the quantum behavior of phonon modes in metallic nanoparticles. Strong vibrational coupling has not been observed in ultra-high frequency mechanical resonators. By engineering phonon dissipation pathways, the authors increase the vibrational quality factor to allow strong coupling observations in plasmonic nanostructures, which has implications for observation and control of quantum phonon dynamics.
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Affiliation(s)
- Junzhong Wang
- College of Electronic Science and Technology, Shenzhen University, Shenzhen, 518060, China
| | - Kuai Yu
- College of Electronic Science and Technology, Shenzhen University, Shenzhen, 518060, China.
| | - Yang Yang
- College of Electronic Science and Technology, Shenzhen University, Shenzhen, 518060, China
| | - Gregory V Hartland
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, IN, 46556, USA
| | - John E Sader
- ARC Centre of Excellence in Exciton Science, School of Mathematics and Statistics, The University of Melbourne, Melbourne, VIC, 3010, Australia
| | - Guo Ping Wang
- College of Electronic Science and Technology, Shenzhen University, Shenzhen, 518060, China.
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Beane G, Devkota T, Brown BS, Hartland GV. Ultrafast measurements of the dynamics of single nanostructures: a review. REPORTS ON PROGRESS IN PHYSICS. PHYSICAL SOCIETY (GREAT BRITAIN) 2019; 82:016401. [PMID: 30485256 DOI: 10.1088/1361-6633/aaea4b] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
The ability to study single particles has revolutionized nanoscience. The advantage of single particle spectroscopy measurements compared to conventional ensemble studies is that they remove averaging effects from the different sizes and shapes that are present in the samples. In time-resolved experiments this is important for unraveling homogeneous and inhomogeneous broadening effects in lifetime measurements. In this report, recent progress in the development of ultrafast time-resolved spectroscopic techniques for interrogating single nanostructures will be discussed. The techniques include far-field experiments that utilize high numerical aperture (NA) microscope objectives, near-field scanning optical microscopy (NSOM) measurements, ultrafast electron microscopy (UEM), and time-resolved x-ray diffraction experiments. Examples will be given of the application of these techniques to studying energy relaxation processes in nanoparticles, and the motion of plasmons, excitons and/or charge carriers in different types of nanostructures.
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Affiliation(s)
- Gary Beane
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, IN 46556, United States of America
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