A voltage tunable quantum dot photodetector for terahertz detection
نویسندگان
چکیده
A voltage tunable quantum dot (QD) photodetector for terahertz detection based on intersublevel transitions is proposed. The intersublevels are formed by the lateral electrical confinement applied on quantum wells and the transitions between them can be strongly tuned by the confinement. Under normal incidence, the peak detection wavelengths can be tuned from ∼50 to ∼90μm (6.0 to ∼3.3 THz) with a gate voltage range of −5 to −2 V. The peak absorption coefficient of detection is in the order of 103 cm−1 at 77 K, and the peak detectivity of the photodetector can reach ∼109 cm2 Hz1/2 W−1. The proposed approach has the advantage of forming a high uniformity of QD effective sizes and provides an alternative way to detect terahertz radiation. (Some figures in this article are in colour only in the electronic version).
منابع مشابه
Modeling of an electrically tunable quantum dot photodetector for terahertz detection
The terahertz region (1-10 THz) has potential applications in many areas, such as chemical sensing, medical imaging and free-space optical communications. With the demonstration of terahertz sources, it is quite necessary to develop the detection technology in terahertz. Here we propose an electrically tunable quantum dot infrared photodetector to detect the terahertz region. The proposed detec...
متن کاملBroadband Ge/SiGe quantum dot photodetector on pseudosubstrate
: We report the fabrication and characterization of a ten-period Ge quantum dot photodetector grown on SiGe pseudosubstrate. The detector exhibits tunable photoresponse in both 3- to 5- μm and 8- to 12- μm spectral regions with responsivity values up to about 1 mA/W at a bias of -3 V and operates under normal incidence radiation with background limited performance at 100 K. The relative respons...
متن کاملVoltage-Controlled Entanglement between Quantum- Dot Molecule and its Spontaneous Emission Fields via Quantum Entropy
The time evolution of the quantum entropy in a coherently driven threelevel quantum dot (QD) molecule is investigated. The entanglement of quantum dot molecule and its spontaneous emission field is coherently controlled by the gat voltage and the intensity of applied field. It is shown that the degree of entanglement between a three-level quantum dot molecule and its spontaneous emission fields...
متن کاملMulti-color tunneling quantum dot infrared photodetectors operating at room temperature
Quantum dot structures designed for multi-color infrared detection and high temperature (or room temperature) operation are demonstrated. A novel approach, tunneling quantum dot (T-QD), was successfully demonstrated with a detector that can be operated at room temperature due to the reduction of the dark current by blocking barriers incorporated into the structure. Photoexcited carriers are sel...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
عنوان ژورنال:
دوره شماره
صفحات -
تاریخ انتشار 2010