Up to 70 THz bandwidth from an implanted Ge photoconductive antenna excited by a femtosecond Er:fibre laser

• 作者: Abhishek Singh Alexej Pashkin Stephan Winnerl Malte Welsch Cornelius Beckh Philipp Sulzer Alfred Leitenstorfer Manfred Helm Harald Schneider
• 来源期刊: 光：科学与应用（英文版）
• 年，卷（期）: 2020,（2）
• 所属期刊栏目: Original Articles
• 页码范围: 293-299
• 页数: 7页
• 语种: 英文

摘要

Phase-stable electromagnetic pulses in the THz frequency range offer several unique capabilities in time-resolved spectroscopy. However, the diversity of their application is limited by the covered spectral bandwidth. In particular, the upper frequency limit of photoconductive emitters-the most widespread technique in THz spectroscopy–reaches only up to 7 THz in the regular transmission mode due to absorption by infrared-active optical phonons. Here, we present ultrabroadband (extending up to 70 THz) THz emission from an Au-implanted Ge emitter that is compatible with mode-locked fibre lasers operating at wavelengths of 1.1 and 1.55μm with pulse repetition rates of 10 and 20 MHz, respectively. This result opens up the possibility for the development of compact THz photonic devices operating up to multi-THz frequencies that are compatible with Si CMOS technology.