Optical Characteristics Analysis of Resonant Tunneling Diode Photodiode Based Oscillators

Abstract

This paper represents the experimental results of optical modulation characteristics of a resonant tunneling diodephotodiode (RTD-PD) device and novel microwave oscillators employing such RTD-PD. Different from a pure electronic RTD oscillator, the RTD-PDs in this work contain photoconductive layers which make it able to operate in optical conditions. A beam of intensity modulated light with a wavelength of 1310 nm was sent to the free running oscillator via an optical fiber whilst the RTD device was biased in the oscillation condition, and the corresponding electrical data can be extracted from the output port of the oscillator. A square wave signal at data rates up to 10 Gbit/s, and a pseudo random binary sequence (PRBS) signal with a data rate of 100 Mbit/s were preliminarily implemented for modulation.

Analysis of Excitability in Resonant Tunneling Diode-Photodetectors

“…Such an I-V curve shift towards lower voltages manifests a large part of the injected light is absorbed in the collector side of the device, leading to charge accumulation (particularly holes) adjacent to the collector-side barrier. Due to the existence of the resistance, which is designed as a stabilizing shunt resistor to suppress the low-frequency bias oscillations [ 2 , 28 ], the NDR region, as well as the light-induced I-V shift, is not pronounced. The RTD-PD operates in its self-oscillation state when the RTD is biased in the NDR region.…”

“…Optoelectronic integrated circuits (OEICs) based on III-V semiconductor resonant tunnelling diodes (RTDs) achieve enhanced functionality in combination with optoelectronic devices, such as photodetectors [ 1 , 2 , 3 ], optical modulators [ 4 ], and lasers [ 5 , 6 ]. The negative differential resistance (NDR) of RTDs provides the intrinsic power gain, which can reduce the employment of extra complex transceiver building blocks [ 7 , 8 ] and makes the systems both compact and energy-efficient.…”

Tunable presynaptic weighting in optoelectronic spiking neurons built with laser-coupled resonant tunneling diodes

“…When biasing an RTD in its NDC region, which exhibits an extensive bandwidth, one can observe self-oscillations with the frequency determined by the RTD and the peripheral circuit elements. Studies of RTDbased oscillators have demonstrated a wide range of oscillation frequencies from tens of GHz [29] to the highest reported 1.98 THz [30]. A range of RTD-based electrical/photonic devices has been investigated to emulate the dynamical properties of biological neurons, and some of the dynamical features, such as excitability and refractoriness, have been confirmed in RTD devices, rendering them as a viable solution for controllable spiking generators [22,[31][32][33][34].…”

Optical direct intensity modulation of a 79GHz resonant tunneling diode-photodetector oscillator

“…RTD-PDs can operate in two modes: non-oscillating (steady state) or oscillating regimes, depending on the operating point. When biased in the positive differential conductance (PDC) region of the I-V curve, the RTD-PD shows similar functionality to a normal photodetector which can absorb the intensity modulated optical signal and covert it to an electrical signal [12]. When the RTD-PD is biased in the NDC region, it operates in the oscillatory mode which gives rise to an electrical gain and high frequency self-sustained oscillations.…”