A novel source of continuous-wave terahertz radiation based on difference frequency generation (DFG) in GaAs crystal is proposed. Phase matching is provided using integration of appropriate optical and terahertz waveguides based on dispersive properties of GaAs. The output frequency can be tuned between 0-3.5 THz by tuning the incident wavelengths in the range of 1.5-1.6 microm.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1364/oe.16.010427 | DOI Listing |
Nanomaterials (Basel)
January 2025
Key Laboratory of Optoelectronic Materials and Devices, Institute of Semiconductors, Chinese Academy of Sciences, Beijing 100083, China.
Antimonide laser diodes, with their high performance above room temperature, exhibit significant potential for widespread applications in the mid-infrared spectral region. However, the laser's performance significantly degrades as the emission wavelength increases, primarily due to severe quantum-well hole leakage and significant non-radiative recombination. In this paper, we put up an active region with a high valence band offset and excellent crystalline quality with high luminescence to improve the laser's performance.
View Article and Find Full Text PDFJ Biomed Opt
January 2025
CIFICEN (UNCPBA - CICPBA - CONICET), Tandil, Argentina.
Significance: In the last years, time-resolved near-infrared spectroscopy (TD-NIRS) has gained increasing interest as a tool for studying tissue spectroscopy with commercial devices. Although it provides much more information than its continuous wave counterpart, accurate models interpreting the measured raw data in real time are still lacking.
Aim: We introduce an analytical model that can be integrated and used in TD-NIRS data processing software and toolkits in real time.
Sci Rep
January 2025
College of Computer Science and Engineering, Northwest Normal University, Lanzhou, 730070, Gansu, China.
Heart disease is a significant global health issue. Traditional methods for heart rate monitoring typically require close physical contact, which limits the continuity and convenience of monitoring. To achieve real-time, non-contact heartbeat monitoring, researchers have introduced millimeter-wave radar technology.
View Article and Find Full Text PDFNatl Sci Rev
February 2025
Institute of Nanoscience and Applications, Department of Electrical and Electronic Engineering, Southern University of Science and Technology, Shenzhen 518055, China.
Colloidal quantum dots (QDs) are solution-processable semiconductor nanocrystals with favorable optoelectronic characteristics, one of which is their multi-excitonic behavior that enables broadband polychromatic light generation and amplification from monodisperse QDs. However, the practicality of this has been limited by the difficulty in achieving spatial separation and patterning of different colors as well as the high pumping intensity required to excite the multi-excitonic states. Here, we have addressed these issues by integrating monodisperse QDs in multi-excitonic states into a specially designed cavity, in which the QDs exhibit an anisotropic polychromatic emission (APE) characteristic that allows for tuning the emission from green to red by shifting the observation direction from perpendicular to lateral.
View Article and Find Full Text PDFMagn Reson Med
January 2025
Advanced Research Promotion Center, Health Sciences University of Hokkaido, Ishikari, Japan.
Purpose: Redox homeostasis plays a key role in regulating the overall health and development of organisms. This study aimed to develop a compact and mobile continuous-wave (CW) electron paramagnetic resonance (EPR) imager to facilitate stable, highly sensitive fast three-dimensional (3D) whole-body imaging of nitroxide-infused mice.
Methods: A multiturn loop gap resonator with a diameter of 30 mm and length of 35 mm was designed for whole-body EPR imaging.
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!