RESUMO
In this work we present a stand-alone, portable system for high resolution real-time THz imaging. The total weight of the apparatus is less than 15 kg and its physical dimension is of ~(65 cm)3. A quantum cascade laser emitting at 3.4 THz laser based on a third-order distributed feedback cavity is used as source. It operates in continuous-wave at 50 K with more than 1 mW output power and less than 300 mW of power consumption. High resolution real-time THz imaging is reported: resolution of 2.5 times the wavelength is demonstrated.
Assuntos
Aumento da Imagem/instrumentação , Lasers , Sistemas Computacionais , Desenho de Equipamento , Análise de Falha de Equipamento , Imagem TerahertzRESUMO
Edge emitting, terahertz quantum cascade photonic-wire lasers, based on a third order Bragg grating are presented. Devices with a power consumption as low as 300mW, with a single frequency output power of more than 1.5mW are demonstrated. Their maximum operating temperature in continuous-wave mode operation is 110K and the emission is concentrated in a narrow beam (~30 degrees divergence). Larger structure based on the same design show more than 10mW output power and more than 200mW/A slope efficiency at 10K continuous-wave operation.
Assuntos
Lasers , Transferência de Energia , Desenho de Equipamento , Análise de Falha de Equipamento , Fótons , Radiação TerahertzRESUMO
We present distributed-feedback Terahertz quantum cascade lasers operating in a double-metal ring waveguide. High power collimated emission in a single spectral mode is observed in the vertical direction. A double-slit configuration is employed to achieve both good electrical contacts and efficient power out-coupling. The optical properties of the devices are interpreted with the aid of finite element simulations.
RESUMO
We demonstrate high spectral control from surface emitting THz Quantum Cascade Lasers based on a two-dimensional photonic crystal cavity. The perforated top metallic contact acts as an in plane resonator in a tight double-metal plasmonic waveguide providing a strong optical feedback without needing three-dimensional cavity features. The optical far-field patterns do not exhibit the expected symmetry and the shape of the cavity mode. The difference is attributed to a metal surface plasmon mediated light outcoupling mechanism also responsible for the relatively low extraction efficiency.