Short period InGaAs/AlInAs THz quantum cascade laser in thin double metal cavities operating up to 188K

TL;DR

This paper reports a terahertz quantum cascade laser using InGaAs/AlInAs with a double metal cavity, achieving operation up to 188K due to material and design improvements.

Contribution

The study introduces a high-temperature THz quantum cascade laser with a novel two-well design and thin active region, enabling operation at record temperatures for this type of device.

Findings

Operates up to 188K in copper-based double metal waveguides

Achieves maximum current density of 1.4kA/cm$^2$

Operates at 170K with 10% duty cycle due to low Joule heating

Abstract

We present a two-well terahertz (THz) quantum cascade laser designed for high temperature operation based on the InGaAs/AlInAs material system. The lighter effective mass and higher energy barriers increase the gain at high temperatures (T > 150K). When processed in copper-based double metal waveguides the devices show laser action up to a maximum operating temperature of 188K with a maximum current density of 1.4kA/cm$^2$. The low Joule heating due to reduced active region thickness and low electrical bias allows operation at 10% duty cycle up to a temperature of 170K.