Subcycle Nonlinear Response of Doped 4 H Silicon Carbide Revealed by Two-Dimensional Terahertz Spectroscopy

TY - JOUR

T1 - Subcycle Nonlinear Response of Doped 4 H Silicon Carbide Revealed by Two-Dimensional Terahertz Spectroscopy

AU - Tarekegne, Abebe T.

AU - Kaltenecker, Korbinian J.

AU - Klarskov, Pernille

AU - Iwaszczuk, Krzysztof

AU - Lu, Weifang

AU - Ou, Haiyan

AU - Norrman, Kion

AU - Jepsen, Peter U.

PY - 2020

Y1 - 2020

N2 - We investigate single-cycle terahertz (THz) field-induced nonlinear absorption in doped silicon carbide. We find that the nonlinear response is ultrafast, and we observe up to 20% reduction of transmission of single THz pulses at peak field strengths of 280 kV/cm. We model the field and temperature dependence of the nonlinear response by a finite-difference time-domain simulation that incorporates the temporally nonlocal nonlinear conductivity of the silicon carbide. Nonlinear two-dimensional THz spectroscopy reveals that the nonlinear absorption has an ultrafast subpicosecond recovery time, with contributions from both sum-frequency generation and four-wave mixing, in the form of a photon-echo signal. The ultrafast nonlinearity with its equally fast recovery time makes silicon carbide an interesting candidate material for extremely fast nonlinear THz modulators.

AB - We investigate single-cycle terahertz (THz) field-induced nonlinear absorption in doped silicon carbide. We find that the nonlinear response is ultrafast, and we observe up to 20% reduction of transmission of single THz pulses at peak field strengths of 280 kV/cm. We model the field and temperature dependence of the nonlinear response by a finite-difference time-domain simulation that incorporates the temporally nonlocal nonlinear conductivity of the silicon carbide. Nonlinear two-dimensional THz spectroscopy reveals that the nonlinear absorption has an ultrafast subpicosecond recovery time, with contributions from both sum-frequency generation and four-wave mixing, in the form of a photon-echo signal. The ultrafast nonlinearity with its equally fast recovery time makes silicon carbide an interesting candidate material for extremely fast nonlinear THz modulators.

KW - field-driven tunnelling

KW - multidimensional spectroscopy

KW - nonlinear response

KW - silicon carbide

KW - terahertz spectroscopy

KW - ultrabroadband spectroscopy

UR - https://www.scopus.com/pages/publications/85076808931

U2 - 10.1021/acsphotonics.9b01462

DO - 10.1021/acsphotonics.9b01462

M3 - Journal article

AN - SCOPUS:85076808931

SN - 2330-4022

VL - 7

SP - 221

EP - 231

JO - ACS Photonics

JF - ACS Photonics

IS - 1

ER -