Bulletin of the American Physical Society
APS March Meeting 2020
Volume 65, Number 1
Monday–Friday, March 2–6, 2020; Denver, Colorado
Session W65: Superlattices and Nanostructures IV: Polaritons and Plasmons |
Hide Abstracts |
Sponsoring Units: DCMP Chair: GuangXin Ni, Columbia Univ Room: Mile High Ballroom 4F |
Friday, March 6, 2020 8:00AM - 8:12AM |
W65.00001: Calibration of long-lifetime polariton structures Jonathan Beaumariage, Zheng Sun, Mark Steger, David M Myers, Shouvik Mukherjee, David Wayne Snoke, Loren Pfeiffer, Kenneth West In short-lifetime polariton samples both the upper and lower polariton branches can be resolved through white light reflectivity. However, in long-lifetime polariton samples the linewidths are so narrow that they can not be resolved through typical spectroscopy. Additionally, photoluminescence from the upper polaritons can often not be seen at relevant detunings, as the upper polaritons quickly drop down to lower polariton states. As such, the calibration of long-lifetime polariton samples is uniquely challenging compared to short-lifetime polariton samples. In this work, we will show various measurements which demonstrate the cavity lifetime is 100 ps or more, and use this collective set of information to create an accurate calibration of the long-lifetime polariton samples. |
Friday, March 6, 2020 8:12AM - 8:24AM |
W65.00002: Dynamics of an Exciton-Polariton Condensate in a Tilted Ring Microcavity Shouvik Mukherjee, Valerii K. Kozin, Anton V. Nalitov, Ivan A. Shelykh, Zheng Sun, David M Myers, Burcu Ozden, Jonathan Beaumariage, Loren Pfeiffer, Kenneth West, Andrew Daley, David Wayne Snoke We have created polariton condensates in a semiconductor microcavity with a lifetime greater than the equilibration time scale for the system at cryogenic temperature (below 10 K). By etching the microcavity into ring micro-channels of width 15 μm we confined the condensate to flow in a circular trap. We have directly imaged the motion of the condensate in the ring using time-resolved optical microscopy techniques. We study both the dynamical and the steady-state regime and present quantitative bounds on the strength of the interactions between polaritons in this system. We also measure the spatial coherence of the condensate in these micro-channels leading to important implications for scaling such networks of micro-channels for simulating NP-hard problems. |
Friday, March 6, 2020 8:24AM - 8:36AM |
W65.00003: Pushing Photons with Electrons: Observation of the Polariton Drag Effect Qi Yao, David M Myers, Burcu Ozden, Jonathan Beaumariage, Loren Pfeiffer, Kenneth West, David Wayne Snoke Exciton-polaritons are quasiparticles that are a superpositions of excitons and photons. In a microcavity, exciton-polaritons have an effective mass and can form a Bose-Einstein condensate (BEC). Experimentally, this condensate can be generated by pumping light into a microcavity structure with quantum wells at the antinodes of the light field, and then we can measure the the energy, real-space and momentum-space distributions of the polaritons using the light they emit, using conventional optical methods. |
Friday, March 6, 2020 8:36AM - 8:48AM |
W65.00004: Observation of the amplitude mode in a microcavity polariton condensate driven by quantum fluctuations Mark Steger, Ryo Hanai, Alexander Edelman, Peter B Littlewood, David Wayne Snoke, Jonathan Beaumariage, Brian Fluegel, Kenneth West, Loren Pfeiffer, Angelo J Mascarenhas We directly observe emission into the amplitude mode from an exciton-polariton condensate: the signature of this mode being the ghost-branch photoluminescence at energies below the condensate. This amplitude mode, the number-fluctuation variant of the Goldstone mode, appears in many forms of condensed matter; however, the polariton system gives a unique way to passively monitor this mode in the steady-state system without driving the population far out of equilibrium. This mode is predicted to manifest as an excitation of condensed particles into the upper-polariton state. Here we present experimental results in agreement with our theoretical analysis. Additionally, we present a family of ghost-branch modes that require an expanded theory to capture. |
Friday, March 6, 2020 8:48AM - 9:00AM |
W65.00005: Hyperbolic phonon polaritons in calcite for nanoscale infrared confinement Vanessa Breslin, Daniel Ratchford, Alexander Giles, Adam Dunkelberger, Jeffrey Owrutsky Phonon-polaritons are collective oscillations resulting from the coupling of photons with optical phonons in polar materials and are supported within a material-specific spectral region called the Reststrahlen band, which is bounded by the transverse and longitudinal optical phonons. In this region, the material behaves optically like a metal due to the negative real part of the permittivity, resulting in the incident light being strongly reflected. When polar materials are nanostructured, phonon-polaritons can enable a variety of near-field optical effects such as sub-diffraction light confinement. Interestingly, a polar material which supports phonon-polaritons can also have anisotropic optical properties, such that different components of its permittivity tensor have opposite signs. These materials are referred to as hyperbolic as they behave optically like a dielectric in one direction and like a metal in the other. Here, we report on the observation of hyperbolic phonon-polaritons (HPhPs) in calcite nanopillar arrays, demonstrate the aspect ratio dependence of the HPhP resonance frequencies, and verify our results through comparison to an analytical model. Calcite is an ideal low-loss material for studying HPhPs that could find applications in mid-IR nanophotonic devices. |
Friday, March 6, 2020 9:00AM - 9:12AM |
W65.00006: Creation of partially rotating vortex of polariton condensate by non-resonant Laguerre-Gaussian optical excitation in semiconductor microcavity Daegwang Choi, Min Park, Byoung Yong Oh, Min-Sik Kwon, Suk In Park, Hang Kyu Kang, Sooseok Kang, Jin Dong Song, Hyoungsoon Choi, Yong-Hoon Cho An exciton-polariton is a bosonic quasi-particle formed by a strong coupling between a quantum well exciton and a cavity photon in a semiconductor microcavity. Its bosonic nature offers the ground state condensation and superfluidity that hosts quantized vortices generated by various optical excitation methods. Here, we observed a new method for creating quantized vortices in the polariton superfluid whose vorticity is determine by the orbital angular momentum of a non-resonant Laguerre-Gaussian optical excitation.[1] Moreover, the polariton condensate is found to be in two different energy states, a vortex carrying excited state and the irrotational ground state, which is confirmed by the tomographic interferometer.[2] As a result, only a part of superfluid is found to be rotating with a vortex core and the fraction of the rotating superfluid can be controlled by changing the excitation beam size or the pumping power. This striking observation will be helpful for improving our understanding of relaxation process and non-equilibrium physics in semiconductor and non-equilibrium superfluid. |
Friday, March 6, 2020 9:12AM - 9:24AM |
W65.00007: Topological Surface-plasmon-polariton Modes on Biharmonic Metal-dielectric Gratings Thomas Smith, Alessandro Principi The area of topological plasmonics is a relatively new and rather unploughed field. The majority of progress thus far has been in constructing crystal structures whose atomic sites take the form of an array of metallic nanoparticles. Such nanoparticles are capable of hosting localised plasmon-polariton modes, which form the basis upon which a tight-binding model may be generated. Through this model, the topological character of the lattice may be probed. A similar result may be arrived at by considering surface-plasmon-polariton resonances on biharmonic metal-dielectric gratings. In such a case, provided that the surface is smooth and has a parabolic profile, the amplitude of the SPP mode may be described by an emergent 1D Schrödinger equation. This equation may then be made to mimic the SSH model through a suitable manipulation of the physical parameters of the system. Then topological states may be observed within the basic scattering formalism, whose existance and character are then confirmed through a tight-binding model. |
Friday, March 6, 2020 9:24AM - 9:36AM |
W65.00008: Photonic crystal for graphene plasmons Lin Xiong, Carlos Forsythe, Minwoo Jung, Alexander McLeod, Yutao Li, Shuai Zhang, Yinan Dong, Song Liu, Michael M Fogler, James H. Edgar, Gennady Shvets, Cory Dean, Dimitri Basov Graphene surface plasmon polaritons (SPPs) are hybrid excitations of electrons and photons which can be controlled by the optical properties of graphene. Periodically varying the optical properties results in a photonic crystal for graphene SPPs. Here we utilize cryogenic near-field optical microscopy to study the band structure induced by a graphene photonic crystal consisting of a high-mobility graphene atop a patterned SiO2 dielectric layer [Xiong, Nat. Commun. 10: 4780 (2019)]. Gating through the dielectric provides a periodic field effect that spatially modulates local carrier densities [Forsythe, Nat. Nanotech. 13, 566–571 (2018)] and the propagation of plasmon polaritons through the graphene. A full plasmonic bandgap and characteristic SPP propagation properties are revealed. Selective engineering of domain wall in the middle of the photonic crystal produces localized SPP modes propagating strictly along the domain wall. These findings signify a new route towards designer-engineered band-structures to route and manipulate highly confined plasmons within high mobility graphene devices. |
Friday, March 6, 2020 9:36AM - 9:48AM |
W65.00009: Plasmon resonance shift and near electric field of silver nanoparcticles: Theoretical analysis of size, shape, and aggregation effects. Masafuyu Matsui, Hisao Nakamura We develop theoretical method to analyze optical response of nanoparticles by combining with discrete dipole approximation. To clarify microscopic level mechanism of plasmon resonance and near field effect, the induced dipole is decomposed into contributions from the electric field by incident light (an incident light term) and that by the induced dipole oscillations (a dipole-dipole interaction term). We examine our theoretical approach to silver nanoparticles and analyze size, shape-dependence of optical response as well as effect of aggregation. The analysis quantitatively reveals that the incident light term dominates the plasmon resonance along the direction of the small diameter whereas the dipole-dipole interaction term is dominant in that of the large diameter. To show effect of aggregation to optical response, we calculate total optical response of interacting two nanospheres. The plasmon resonance along the direction, on which two spheres are aligned, is caused by an interparticle interaction, resulting in the similar behavior to the prolate nanospheroid. These results indicate usefulness of modeling of the optical response of multi-nanoparticles by that of a shape-anisotropic nanoparticle. |
Friday, March 6, 2020 9:48AM - 10:00AM |
W65.00010: Size tunable passive cloaking platform using self-assembled plasmonic nanostructures.
Imran Khan,1 Arnold Kim,2 and Sayantani Ghosh1
1Department of Physics, University of California, Merced, CA 95343 USA
2Department of Applied Mathematics, Univ Imran Khan, Arnold D.Kim, Sayantani Ghosh Plasmonic cloaking works by suppressing dominant scattering harmonics radiated from the cloaked object. A shell made of plasmonic nanoparticles (NPs), in combination with the cloaked object as a core, creates the complete plasmonic cloaking structure. In this study, we present the design and fabrication of spherical nano- to micron-scale shell structures via molecular self-assembly of gold NPs, with the goal of reduced scattering and therefore, cloaking, in the VIS-NIR spectral range. Scattering suppression range is varied by tuning the critical parameters of the effective medium, such as core to shell radius ratio and the filling fraction of the NPs in the shell wall. In addition to experimental work, we have also developed a multiscale simulation platform that explicitly models multiple scattering by the gold NPs and their multiple interactions with the core. Simulation results shows that the nano-assembled spheres yield suppressed visibility in the desired spectral range. |
Follow Us |
Engage
Become an APS Member |
My APS
Renew Membership |
Information for |
About APSThe American Physical Society (APS) is a non-profit membership organization working to advance the knowledge of physics. |
© 2024 American Physical Society
| All rights reserved | Terms of Use
| Contact Us
Headquarters
1 Physics Ellipse, College Park, MD 20740-3844
(301) 209-3200
Editorial Office
100 Motor Pkwy, Suite 110, Hauppauge, NY 11788
(631) 591-4000
Office of Public Affairs
529 14th St NW, Suite 1050, Washington, D.C. 20045-2001
(202) 662-8700