Monolithically Integrated Optoelectronic Terahertz Sources and Detectors on Quantum Well PIN Substrates

We present a monolithically integrated terahertz optoelectronics (MITO) platform utilizing quantum well (QW) PIN photodiodes, which accommodates terahertz sources, detectors, optical pump sources, amplifiers, modulators, filters, and passive components on a single chip, for the first time. We demonstrate tunable signal generation and detection over 0.1-0.5 THz through photomixing in QW PIN photodiodes and achieve substantial improvements in power efficiency and sensitivity compared to previous devices. This MITO platform can be realized through photonic integrated circuit foundry processes, paving the way for widespread adoption of terahertz optoelectronic systems beyond laboratory settings. It would enable practical applications in remote sensing, communications, and medical diagnostics within portable devices.