Nonlinear Optical Observation of Coherent Acoustic Dirac Plasmons in Thin-Film Topological Insulators

Abstract

Low-energy collective electronic excitations exhibiting sound-like linear dispersion have been intensively studied both experimentally and theoretically for a long time. However, coherent acoustic plasmon modes appearing in time-domain measurements are rarely observed due to Landau damping by the single-particle continua. Here we report on the observation of coherent acoustic Dirac plasmon (CADP) modes excited in indirectly (electrostatically) opposite-surface coupled films of the topological insulator Bi2Se3. Using transient second harmonic generation, a technique capable of independently monitoring the in-plane and out-of-plane electron dynamics in the films, the GHz-range oscillations were observed without corresponding oscillations in the transient reflectivity. These oscillations were assigned to the transverse magnetic and transverse electric guided CADP modes induced by the evanescent guided Lamb acoustic waves and remained Landau undamped due to fermion tunneling between the opposite-surface Dirac states.

References in corpus (28)

• Topological Insulators
• Theory of surface plasmons and surface-plasmon polaritons
• Crossover of Three-Dimensional Topological Insulator of Bi2Se3 to the Two-Dimensional Limit
• Phase transition between the quantum spin Hall and insulator phases in 3D: emergence of a topological gapless phase
• Coexistence of the topological state and a two-dimensional electron gas on the surface of Bi2Se3
• Bulk Fermi surface coexistence with Dirac surface state in Bi${}_2$Se${}_3$: a comparison of photoemission and Shubnikov-de Haas measurements
• Observation of Dirac plasmons in a topological insulator
• Plasmonics in Dirac systems: from graphene to topological insulators
• Exotic plasmon modes of double layer graphene
• Direct Optical Coupling to an Unoccupied Dirac Surface State in the Topological Insulator Bi${}_2$Se${}_3$
• Selective probing of photo-induced charge and spin dynamics in the bulk and surface of a topological insulator
• Efficient nonlinear generation of THz plasmons in graphene and topological insulators
• Nonlinear optical probe of tunable surface electrons on a topological insulator
• Ultrafast carrier dynamics in thin-films of the topological insulator Bi2Se3
• Emergence of decoupled surface transport channels in bulk insulating Bi2Se3 thin films
• Double-layer graphene and topological insulator thin-film plasmons
• Plasmons in coupled bilayer structures
• Theory of acoustic surface plasmons
• Acoustic plasmons in extrinsic free-standing graphene
• Effect of carrier recombination on ultrafast carrier dynamics in thin films of the topological insulator Bi2Se3
• Thermoelectric performance of classical topological insulator nanowires
• Acoustic phonon dynamics in thin-films of the topological insulator Bi2Se3
• Resonance-type thickness dependence of optical second harmonic generation in thin-films of the topological insulator Bi2Se3
• Plasmon-enhanced electron-phonon coupling in Dirac surface states of the thin-film topological insulator Bi2Se3
• Ab initio calculation of low-energy collective charge-density excitations in MgB2
• Effect of Mn doping on ultrafast carrier dynamics in thin films of the topological insulator Bi2Se3
• Resonant plasmon-phonon coupling and its role in magneto-thermoelectricity in bismuth
• Time-resolved second harmonic generation study of buried semiconductor heterointerfaces using soliton-induced transparency

Cited by in corpus (13)

• Anomalous Acoustic Plasmon Mode from Topologically Protected States
• Terahertz tuning of Dirac plasmons in Bi${}_2$Se${}_3$ Topological Insulator
• Clarifying ultrafast carrier dynamics in ultrathin films of the topological insulator Bi2Se3 using transient absorption spectroscopy
• Tunable Intrinsic Plasmons due to Band Inversion in Topological Materials
• Topologically Nontrivial Interband Plasmons in Type-II Weyl Semimetal MoTe${}_2$
• Coherent surface-to-bulk vibrational coupling in the 2D topologically trivial insulator Bi2Se3 monitored by ultrafast transient absorption spectroscopy
• Dynamic Opening of a Gap in Dirac Surface States of the Thin-Film 3D Topological Insulator Bi2Se3 Driven by the Dynamic Rashba Effect
• Multiphoton-pumped UV-Vis transient absorption spectroscopy of 2D materials: basic concepts and recent applications
• Ultrafast transient absorption spectroscopy of 2D semiconductors: a review
• Two-photon IR pumped UV-Vis transient absorption spectroscopy of Dirac fermions in the 2D and 3D topological insulator Bi2Se3
• Toward Monoatomic-Layer Field Confinement Limit via Acoustic Graphene Plasmons
• Chiral edge plasmons in quantum anomalous Hall insulators
• Distinguishing between dynamical and static Rashba effects in hybrid perovskite nanocrystals using transient absorption spectroscopy