THz Electronics for Data Centre Wireless Links - the TERAPOD Project

This paper presents an overview of the terahertz (THz) resonant tunneling diode (RTD) technology that will be used as one of the approaches towards wireless data centres as envisioned on the eU H2020 TERAPOD project. We show an example 480 gm × 680 gm THz source chip at 300 GHz employing a 4 gm × 4 gm RTD device with 0.15 mW output power. We also show a basic laboratory wireless setup with this device in which up to 2.5 Gbps (limited by equipment) was demonstrated

IV Characteristics of a Stabilized Resonant Tunnelling Diodes

The presence of parasitic oscillations found in the negative differential region (NDR), which can distort the current-voltage (I-V) characteristics of the device is one of the main problems when designing resonant tunnelling diode (RTD) circuits. A new method for RTD stabilization is proposed based on work done previously on tunnel diodes and results show that there is a significant difference between the I-V characteristics of a tunnel diode and that of an RTD. This work shows promising potential for further increasing the RTD’s output power, DC-RF conversion efficiency and provides the basis for an accurate model of the NDR regio

Resonant tunnelling diode based high speed optoelectronic transmitters

Resonant tunneling diode (RTD) integration with photo detector (PD) from epi-layer design shows great potential for combining terahertz (THz) RTD electronic source with high speed optical modulation. With an optimized layer structure, the RTD-PD presented in the paper shows high stationary responsivity of 5 A/W at 1310 nm wavelength. High power microwave/mm-wave RTD-PD optoelectronic oscillators are proposed. The circuitry employs two RTD-PD devices in parallel. The oscillation frequencies range from 20-44 GHz with maximum attainable power about 1 mW at 34/37/44GHz.European Commission [645369

Compact J-band Oscillators with 1 mW RF Output Power and over 110 GHz Modulation Bandwidth

We report a compact resonant tunneling diode (RTD) oscillator with 1 mW output power at 260 GHz and a modulation bandwidth of over 110 GHz. The oscillator employs an RTD device size of 4 × 4 μm 2 resonating with an 88 μm long microstrip inductor. The total chip size is 470 × 530 μm 2. All fabrication was done using the low cost photolithography technique

Loading Effect of W-band Resonant Tunneling Diode Oscillator by Using Load-Pull Measurement

Resonant tunneling diode (RTD) is the fastest solid-state electronic device with the highest reported frequency at 1.92 THz [1]. RTD-based THz sources have many promising applications such as ultrafast wireless communications, THz imaging, etc. To date, the main limitation of RTD technology is the low output power. Many efforts had been made to increase the power level by such as optimizing the layer structure [2], employing more devices in an array [3], matching impedance by displacing the device in circuit [3], etc. Here we report the loading effect by using E/H impedance tuner. We found that the maximum power is over 20dB higher than the worst impedance matching and the frequency shift is within 14% range of the central frequency. The load-pull measurement provides a convenient way to investigate the power/frequency variation versus the impedance change. Further work will benefit from the measurement results to design corresponding impedance matching network. The power level of RTD oscillator will be increased

Resonant tunneling diode oscillators for optical communications

The ability to use resonant tunneling diodes (RTDs) as both transmitters and receivers is an emerging topic, especially with regards to wireless communications. Successful data transmission has been achieved using electronic RTDs with carrier frequencies exceeding 0.3 THz. Specific optical-based RTDs, which act as photodetectors, have been developed by adjusting the device structure to include a light absorption layer and small optical windows on top of the device to allow direct optical access. This also allows the optical signal to directly modulate the RTD oscillation. Both types of RTD oscillators will allow for seamless integration of high frequency radio and optical fiber networks.European Union's Horizon research and innovation programme [645369

Mm-wave/THz Multi-Gigabit Wireless Links

This paper presents millimetre-wave (nm-wave) and terahertz (THz) multi-gigabit wireless links which use planar integrated circuit high power resonant tunnelling diode (RTD) oscillators as transmitters. By employing appropriate circuitry and improved device epilayer design, the oscillators generate an output power of 2 mW at 84 GHz and 1 mW at 206 GHz, respectively, which are the highest reported output powers for RTD-based oscillators at the respective frequencies. Preliminary wireless communication results show 15 Gbps and 13 Gbps data rates over distances of about half a meter

Resonant Tunneling Diode Oscillator Source for Terahertz Applications

Resonant tunneling diode (RTD) is the fastest solid-state electronic device with the highest reported frequency at 1.92 THz [1]. RTD-based THz sources have many promising applications such as ultrafast wireless communications, THz imaging, etc. To date, the main limitation of RTD technology is the low output power. Here we report the series of nearly/over one half mW output power RTD oscillator. The frequencies range from 125 GHz to 308 GHz and the preliminary wireless communication measurement result demonstrates data rate up to 7Gbps

15 Gb/s 50-cm wireless link using a high power compact III-V 84 GHz transmitter

This paper reports on a 15-Gb/s wireless link that employs a high-power resonant tunneling diode (RTD) oscillator as a transmitter (Tx). The fundamental carrier frequency is 84 GHz and the maximum output power is 2 mW without any power amplifier. The reported performance is over a 50-cm link, with simple amplitude shift keying modulation utilized. The 15-Gb/s data link shows correctable bit error rate (BER) of 4.1 x 10⁻³, while the lower data rates of 10 and 5 Gb/s show a BER of 3.6 x 10⁻⁴ and 1.0 x 10⁻⁶, respectively. These results demonstrate that the RTD Tx is a promising candidate for the next-generation low-cost, compact, ultrahigh data rates wireless communication systems

Anti-endometriotic effect of Angelica sinensis (Oliv.) Diels extract in human endometriotic cells and rats

Purpose: To study the anti-endometriotic effect of Angelica sinensis (Oliv.) Diels extract (ASDE) in human endometriotic cells and rats.Method: Forty female rats were randomly divided into four groups (10 rats/group): control, endometriosis+danazol, endometriosis+high dose of ASDE and low dose of ASDE. The rats were orally administered either vehicle (200 μL of PBS) alone or ASDE (140, 280 and 560 mg/kg/day) for 5 weeks. Danazol was used as the control drug. After induction of endometriosis for 4 weeks, the rats were sacrificed by cervical dislocation and the peritoneum and visceral organs examined visually to measure the number of endometriotic lesions. Serum levels of cancer antigen 125 (CA-125) and interleukin 13 (IL-13), interleukin 18 (IL-18) and tumor necrosis factor-alpha (TNF-α) of peritoneal fluids of rats were measured using ELISA kits. Western blot assay was performed to measure the levels of matrix metalloproteinase-2 (MMP-2) and matrix metalloproteinase-9 (MMP-9)  expressions after 24 h of treatment with ASDE (30, 60, and 120 μg/mL).Results: ASDE-treated rats displayed reduced numbers of total endometriotic lesions when compared with vehicle-treated controls (p < 0.01). When the rats were treated with high dose of ASDE, serum CA-125 level, as well as IL-18 and TNF-α levels in peritoneal fluids were significantly lower than that of the control group (p < 0.01); however, IL-13 level in peritoneal fluids was significantly higher than that of the control group (p < 0.01). ASDE treatment significantly suppressed the levels of MMP-2 and MMP-9 protein in 11Z cell (p < 0.01).Conclusion: The results reveal that ASDE exhibits significant anti-endometriotic effect by inhibiting inflammatory factors in rats. Thus, the plant extract can potentially be developed for the clinical management of endometriosis. Keywords: Angelica sinensis, Endometriosis, Cancer antigen, Endometriotic lesions, Matrix metalloproteinas