THz Transceiver with 6.5 THz Bandwidth

Abstract

A terahertz (THz) transceiver, containing emitter and receiver on a compact single chip, simplifies reflection measurements in THz time-domain spectroscopy (TDS) considerably [1]. This is because a collinear geometry allows for variable working distances and increases alignment tolerances. Until today, separate emitters and receivers are commonly used in reflection measurements. In this configuration, the collinear geometry necessitates a beam splitter, which reduces the detected power drastically: For a 50:50 beam splitter, the detected THz power is reduced to only 25%. Therefore, a compact, integrated THz transceiver is highly desirable [1]. In this paper, we present an optimized, monolithically integrated THz transceiver based on iron (Fe) doped InGaAs (InGaAs:Fe). With a dynamic range of up to 80 dB and a bandwidth of 6.5 THz, this transceiver shows a performance comparable to individual, state-of-the-art emitters and receivers [2]. Due to optical fiber coupling, the transceiver is directly compatible with existing THz TDS systems.