2021/03/31 by Høgni C. Kamban, Thomas Garm Pedersen, Thomas G. Pedersen
Engineering · Physics and Astronomy · #Atomic physics #Condensed matter physics #Exciton #Ion #Ionization #Materials science #Optoelectronics #Physics #Quantum mechanics #Semiconductor Quantum Structures and Devices #Strong Light-Matter Interactions #Terahertz radiation #Terahertz spectroscopy and technology #Terahertz technology and applications #cond-mat.mes-hall #cond-mat.mtrl-sci
paper · pdf · doi:10.1103/physrevb.104.235305
arxiv created 2021/08/11 · openalex publication_date 2021/12/20 · arxiv updated 2022/01/05 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/06
External electric fields are highly attractive for dynamical manipulation of excitons in two-dimensional materials. Here, we theoretically study the ionization of excitons in monolayer transition metal dichalcogenides (TMDs) by intense pulsed electric fields in the terahertz (THz) regime. We find that THz pulses with realistic field strengths are capable of ionizing a significant fraction of photogenerated excitons in TMDs into free charge carriers. Short THz pulses are therefore an efficient, noninvasive method of dynamically controlling the free carrier concentration in monolayer TMDs, which is useful for applications such as THz modulators. We further demonstrate that exciton ionization probabilities should be experimentally measurable by comparing free carrier absorption before and after the THz pulse. Detailed results are provided for different TMDs in various dielectric environments.