Efficient terahertz generation and detection in cadmium telluride using ultrafast ytterbium laser

Abstract

In this work, we study THz generation and detection using cadmium telluride (CdTe) crystals pumped by amplified (1.025 μm wavelength) and oscillator (1.045 μm wavelength) ytterbium (Yb) lasers. For each laser, we compare the performances of the CdTe THz emitter and detector to those of GaP crystals. Under optimum conditions, we demonstrate that the former shows 3 and 5 times better performances compared with the latter for detection and generation, respectively. When pumped by an amplified Yb laser, we find that the CdTe crystal is more efficient than the GaP crystal for emission at optical fluences lower than 250 μJ/cm2. Although CdTe has some limitations in comparison with GaP, such as high THz absorption above 1 THz and the appearance of two-photon absorption at relatively low optical intensity, our findings demonstrate the potential of this crystal to be used as the emitter and detector in combination with the Yb laser.

Graphene-based metasurface absorber for the active and broadband manipulation of terahertz radiation

“…Therefore, they can be employed for achieving high-rate data transfer in wireless technology [48]. In view of the useful potential applications of THz radiation, progress has been made in THz generation and detection (see, e.g., [49,50]) as well as in achieving functional metasurfaces for lensing, polarization conversion, splitting, and other applications (see, e.g., [5,7,14]). Employing gold-based metasurfaces integrated with semiconductors as active elements has also been introduced as an efficient method to real-time control and to manipulate THz radiation [51].…”

Investigation of Photoexcitation Energy Impact on Electron Mobility in Single Crystalline CdTe

“…Single crystalline cadmium telluride (SC-CdTe) is considered a promising semiconductor material in many applications, e.g., optoelectronics [ 1 , 2 ], radiation detectors [ 3 , 4 ] and Gunn oscillators [ 5 ]. The material exhibits a high mobility lifetime ( μτ ) product, which is important in order to achieve high spatial resolution and high counting efficiency in detector applications.…”

Broadband heterodyne electro-optic sampling using a lithium niobate ridge-waveguide

“…1) For instance, recent developments in Ytterbium (Yb) lasers operating at 1040 nm are emerging as a convincing alternative to Ti: sapphire (800 nm) lasers for the efficient generation of THz waves. 2) To detect these waves, new EO sampling schemes have been demonstrated at the fundamental and harmonic wavelengths of the Yb laser, using cadmium telluride (CdTe) 3) and zinc sulfide (ZnS), 4) respectively. However, these crystals present limitations, such as strong absorption at 2.1 THz in CdTe 3) and poor crystal uniformity for ZnS.…”

“…2) To detect these waves, new EO sampling schemes have been demonstrated at the fundamental and harmonic wavelengths of the Yb laser, using cadmium telluride (CdTe) 3) and zinc sulfide (ZnS), 4) respectively. However, these crystals present limitations, such as strong absorption at 2.1 THz in CdTe 3) and poor crystal uniformity for ZnS. 4) In addition, these crystals do not operate at the wavelength of the Ti:Sapphire laser.…”