High-Harmonic Generation in Solids with and without Topological Edge States

Abstract

High-harmonic generation in the two topological phases of a finite, one-dimensional, periodic structure is investigated using a self-consistent time-dependent density functional theory approach. For harmonic photon energies smaller than the band gap, the harmonic yield is found to differ by up to 14 orders of magnitude for the two topological phases. This giant topological effect is explained by the degree of destructive interference in the harmonic emission of all valence-band (and edge-state) electrons, which strongly depends on whether or not topological edge states are present. The combination of strong-field laser physics with topological condensed matter opens up new possibilities to electronically control strong-field-based light or particle sources or-conversely-to steer by all optical means topological electronics.

High-harmonic generation in Su-Schrieffer-Heeger chains

“…Topological phases became the focus of research directions such as topological insulators [14][15][16], topological superconductivity [17,18], cold atoms [19], topological photonics [20][21][22], toplogical electronic circuitry [23][24][25], and topological mechanics [26]. Only very recently, the exploration of the physics at the interface between strong-field attosecond science and topological condensed matter began theoretically [27][28][29][30][31][32] and experimentally [33,34]. Of particular interest there is the all-optical distinction of topological phases, the steering of electrons through Berry curvatures or along topologically protected edges on sub-laser-cycle time scales, with potential applications in coherent light-wave electronics [35][36][37][38].…”

“…In Ref. [28], harmonic generation in dimerizing linear chains was investigated using time-dependent density functional theory (TDDFT) [39,40]. A huge difference in the harmonic yield for the topological phases A and B (see Fig.…”

Imperfect Recollisions in High-Harmonic Generation in Solids

“…The last decade has seen the emergence of highharmonic generation (HHG) in solids [1][2][3][4][5][6] as a promising and compact ultrafast light source, as well as a potential tool to reconstruct crystal band structures [7], measure Berry curvatures [8,9], and probe topological phase transitions [10][11][12]. Complementing experimental progress, a number of theoretical studies have explored HHG in solids either in terms of reciprocal-space dynamics within the band structure [1,5,6,[13][14][15][16][17][18][19][20][21][22][23], which contains both intra-and interband contributions, or in terms of realspace particle-like dynamics in the crystal [2,3,14,[24][25][26][27][28][29].…”

High harmonic generation in crystals using maximally localized Wannier functions

“…Since the discovery of high harmonic generation (HHG) in solids [1], several works demonstrate the potential of analyzing the light emitted by bulk electrons in solids when exposed to intense laser fields. Recent results include the observation of dynamical Bloch oscillations [2,3], band structure tomography [4,5], resolving electron-hole dynamics [6,7], including dynamics in strongly correlated systems and phase transitions in the Mott insulator [8], the Peierls phase transition [6], or the imprint of the Berry phase on high harmonic spectrum [9,10].…”