Spontaneous Photon-Emission Spectrum of Tunneling Electrons in a Double-BarrierStructure

摘要

Infrared (IR) photodetectors and lasers are of most importance for many photonicapplications in the optical interconnection, communication, and computation areas. Intersubband transitions in a superlattice or in a multiple-quantum-well structure can be used for a variety of IR detectors and lasers. There are many advantages to using intersubband transitions because the transition energy can be tuned by changing the structure parameters such as the well and barrier width and the barrier height. The theoretical study in this field was initiated over 20 years ago, soon after Esaki and Tsu's original idea of designing a semiconductor superlattice. Kazarinov and Suris addressed the possibility of generation and amplification of infrared light in a superlattice using sequential electron tunneling between adjacent wells. Recently, experimental evidence for optical intersubband absorption and sequential electron tunneling in a quantum-well structure were published. These observations have stimulated further studies in this important areas.