Control of High-Harmonic Generation by Tuning the Electronic Structure and Carrier Injection

Abstract

High-harmonic generation (HHG), which is the generation of light with multiple optical harmonics, is an unconventional nonlinear optical phenomenon beyond the perturbation regime. HHG, which was initially observed in gaseous media, has recently been demonstrated in solid-state materials. Determining how to control such extreme nonlinear optical phenomena is a challenging subject. Here, we demonstrate the control of HHG through tuning the electronic structure and carrier injection using single-walled carbon nanotubes (SWCNTs). We reveal systematic changes in the high-harmonic spectra of SWCNTs with a series of electronic structures ranging from a metal structure to a semiconductor structure. We demonstrate enhancement or reduction of harmonic generation by more than 1 order of magnitude by tuning the electron and hole injection into the semiconductor SWCNTs through electrolyte gating. These results open a path toward the control of HHG in the context of field-effect transistor devices.

Doping and gap-size dependence of high-harmonic generation in graphene : Importance of consistent formulation of light-matter coupling

“…Under this correspondence, the excitation frequency corresponds to Ω = 0.26 eV, which is in the midinfrared regime, and our time unit approximately corresponds to 0.66 fs. This set of parameters is motivated by experiments on graphene and carbon nanotubes 18,26 . We also note that we set the bond length (0.246 × 1 √ 3 nm for graphene) as our unit of length and set the charge q to unity.…”

“…One important aspect of condensed matters is the sensitivity of material properties against system parameters such as doping-level and temperature. This feature opens the interesting possibility of controlling HHG in condensed matters using active degrees of freedoms [25][26][27][28] . For example, strong doping dependence of the HHG spectrum has been reported in carbon nanotubes, where the doping level is controlled by gating 26 .…”

“…This feature opens the interesting possibility of controlling HHG in condensed matters using active degrees of freedoms [25][26][27][28] . For example, strong doping dependence of the HHG spectrum has been reported in carbon nanotubes, where the doping level is controlled by gating 26 .…”

High‐Harmonic Generation from 2D Monolayer Electrides

“…202100368 Unlike atoms and molecules, the nonlinear condensed matter provides higher efficiency and enables us to compress the volume of experimental setup. Although HHG from condensed matter has been extensively investigated both theoretically [29][30][31][32][33][34][35][36][37][38][39] and experimentally, [40][41][42][43][44][45][46] the mechanism is still under debate due to the complicated elementary processes. In particular, two-dimensional (2D) monolayers show interesting behaviors: HHG pumped with laser pulses with in-plane polarization behaves similar to the case of solid state medium, while atomic-like HHG is observed for out-of-plane polarized pumping.…”

Carbon Nanotubes for Active Refrigeration and Cooling in Micro and Mesoscale Systems

“…Unfortunately, the potential of carbon nanotubes for micro and mesoscale refrigeration and cooling is not fully explored. With the development of high-k dielectric materials [45][46][47] and the technology of carrier injection, [48][49][50] the tuning of Fermi level and carrier concentration of carbon nanotubes with nanoscale diameters can be realized to traditional unreachable ranges, which may promise higher power density and active rate of refrigeration and cooling. As pointed out by Zebarjadi et al, [51] in many important application environments including satellites and space stations, [52][53][54][55][56] as well as quantum computing and quantum communications, [57][58][59][60] the actual rate for refrigeration and cooling is of much higher priority compared to the efficiency and the cost.…”