Query: “Broadly tunable terahertz generation in mid-infrared quantum cascade lasers

Candidate papers:

abstract: Room temperature, broadly tunable, electrically pumped semiconductor sources in the terahertz spectral range, similar in operation simplicity to diode lasers, are highly desired for applications. An emerging technology in this area are sources based on intracavity difference frequency generation in dual wavelength mid infrared quantum cascade lasers. Here we report terahertz quantum cascade laser sources based on an optimized non collinear Cherenkov difference frequency generation scheme that demonstrates dramatic improvements in performance. Devices emitting at 4 THz display a mid infrared to terahertz conversion efficiency in excess of 0.6 mW W( 2) and provide nearly 0.12 mW of peak power output. Devices emitting at 2 and 3 THz fabricated on the same chip display 0.09 and 0.4 mW W( 2) conversion efficiencies at room temperature, respectively. High terahertz generation efficiency and relaxed phase matching conditions offered by the Cherenkov scheme allowed us to demonstrate, for the first time, an external cavity terahertz quantum cascade laser source tunable between 1.70 and 5.25 THz.
author_names: Karun Vijayraghavan

Yifan Jiang

Min Jang

Aiting Jiang

Karthik Choutagunta

Augustinas Vizbaras

Frederic Demmerle

Gerhard Boehm

Markus-Christian Amann

Mikhail A Belkin
title: Broadly tunable terahertz generation in mid infrared quantum cascade lasers.
venue: Nature communications
year: 2013

author_names: Yifan Jiang
title: Broadly tunable terahertz difference frequency generation in mid infrared quantum cascade lasers
year: 2017

abstract: We report a monolithic terahertz source made of an array of 10 electrically tunable mid infrared quantum cascade lasers with intra cavity terahertz difference frequency generation. Continuous tunability between 2 and 4 THz is demonstrated at room temperature.
author_names: Aiting Jiang

Seungyong Jung

Yifan Jiang

Karun Vijayraghavan

Jae Hyun Kim

Mikhail A Belkin
title: Broadly tunable room temperature monolithic terahertz quantum cascade laser sources
venue: CLEO 2015
year: 2015

abstract: We report a monolithic terahertz source made of an array of 10 electrically tunable mid infrared quantum cascade lasers with intra cavity terahertz difference frequency generation. Continuous tunability between 2 and 4 THz is demonstrated at room temperature.
author_names: Aiting Jiang

Seungyong Jung

Yifan Jiang

Karun Vijayraghavan

Jaehyun Kim

Mikhail A Belkin
title: Broadly tunable room temperature monolithic terahertz quantum cascade laser sources
venue: 2015 Conference on Lasers and Electro Optics (CLEO)
year: 2015

abstract: We present room temperature broadly tunable external cavity terahertz sources based on Cherenkov intra cavity difference frequency generation in mid infrared quantum cascade lasers bonded with Si substrate. Laser chips are integrated into a Littrow type external cavity system. Devices demonstrate continuous THz emission tuning from 1.2 THz to 5.9 THz at room temperature with peak power output varying between 5 and 45 mW, depending on the operating frequency.
author_names: Yifan Jiang

Karun Vijayraghavan

Seungyong Jung

Frederic Demmerle

Gerhard Boehm

Markus-Christian Amann

Mikhail A Belkin
title: Broadly tunable external cavity terahertz source from 1.2~5.9 THz
venue: 2014 39th International Conference on Infrared, Millimeter, and Terahertz waves (IRMMW THz)
year: 2014

abstract: Terahertz quantum cascade laser sources based on intra cavity difference frequency generation are currently the only room temperature mass producible diode laser like emitters of coherent 1 6 THz radiation. Device performance has improved dramatically over the past few years to reach milliwatt level power output and broad tuning from 1.2 to 5.9 THz, all at room temperature. Terahertz output in these sources originates from intersubband optical nonlinearity in the laser active region. Here we report the first comprehensive spectroscopic study of the optical nonlinearity and investigate its dependence on the mid infrared pump frequencies. Our work shows that the terahertz generation efficiency can vary by a factor of 2 or greater depending on the spectral position of the mid infrared pumps for a fixed THz difference frequency. We have also measured for the first time the linewidth for transitions between the lower quantum cascade laser states, which is critical for determining terahertz nonlinearity and predicting optical loss in quantum cascade laser waveguides.
author_names: Yifan Jiang

Karun Vijayraghavan

Seungyong Jung

Aiting Jiang

Jae Hyun Kim

Frederic Demmerle

Gerhard Boehm

Markus-Christian Amann

Mikhail A Belkin
title: Spectroscopic Study of Terahertz Generation in Mid Infrared Quantum Cascade Lasers
venue: Scientific reports
year: 2016

abstract: We report the performance of room temperature terahertz sources based on intracavity difference frequency generation in mid infrared quantum cascade lasers with a dual upper state (DAU) active region. DAU active region design is theoretically expected to produce larger optical nonlinearity for terahertz difference frequency generation, compared to the active region designs of the bound to continuum type used previously. Fabricated buried heterostructure devices with a two section buried distributed feedback grating and the waveguide designed for Cherenkov difference frequency phase matching scheme operate in two single mode mid infrared wavelengths at 10.7 mm and 9.7 mm and produce terahertz output at 2.9 THz with mid infrared to terahertz conversion efficiency of 0.8 mW/W2 at room temperature.
author_names: Kazuue Fujita

Masahiro Hitaka

Akio Ito

Tadataka Edamura

Masamichi Yamanishi

Seungyong Jung

Mikhail A Belkin
title: Terahertz generation in mid infrared quantum cascade lasers with a dual upper state active region
year: 2015

abstract: We discuss novel approaches to improve the tuning bandwidth and power output of terahertz (THz) sources based on difference frequency generation (DFG) in mid infrared quantum cascade lasers (QCLs) Using a double Littrow external cavity system, we experimentally demonstrate that both doubly resonant terms and optical rectification terms in the expression for the intersubband optical nonlinearity contribute to THz generation in DFG QCLs and report THz DFG QCLs with the optimized optical rectification terms. We also demonstrate a hybrid DFG QCL device on silicon that enables significant improvement on THz out coupling efficiency and results in more than 5 times higher THz output power compared to that of a reference device on its native semi insulating InP substrate. Finally, we report for the first time the THz emission linewidth of a free running continuous wave THz DFG QCL.
author_names: Seungyong Jung

Yifan Jiang

Jae Hyun Kim

Luigi Consolino

Saverio Bartalini

Paolo De Natale

Miriam Vitello

Kazuue Fujita

Masahiro Hitaka

Akio Ito

J D Kirch

Dan Botez

Frederic Demmerle

Gerhard Boehm

Markus-Christian Amann

Mikhail A Belkin
title: Narrow linewidth ultra broadband terahertz sources based on difference frequency generation in mid infrared quantum cascade lasers
venue: OPTO
year: 2017

abstract: We discuss novel approaches to improve the tuning bandwidth and power output of terahertz (THz) sources based on difference frequency generation (DFG) in mid infrared quantum cascade lasers (QCLs) Using a double Littrow external cavity system, we experimentally demonstrate that both doubly resonant terms and optical rectification terms in the expression for the intersubband optical nonlinearity contribute to THz generation in DFG QCLs and report THz DFG QCLs with the optimized optical rectification terms. We also demonstrate a hybrid DFG QCL device on silicon that enables significant improvement on THz out coupling efficiency and results in more than 5 times higher THz output power compared to that of a reference device on its native semi insulating InP substrate. Finally, we report for the first time the THz emission linewidth of a free running continuous wave THz DFG QCL.
author_names: Seungyong Jung

Yifan Jiang

Jae Hyun Kim

Luigi Consolino

Saverio Bartalini

Paolo De

Miriam Serena Vitiello

Kazuue Fujita

Masahiro Hitaka

Akio Ito

J D Kirch

Frederic Demmerle

Gerhard Boehm

Markus-Christian Amann

Ayman Mikhail
title: Narrow linewidth ultrabroadband terahertz sources based on difference frequency generation in mid infrared quantum cascade lasers
year: 2017

abstract: We report 5 THz quantum cascade laser sources based on intra cavity difference frequency generation in dual wavelength mid infrared quantum cascade lasers. Our devices produce microwatt level terahertz output at 80 K and approximately 200 nW output at 250 K.
author_names: Mikhail A Belkin

Federico Capasso

Feng Xie

Alexey Belyanin

Milan Fischer

Andreas Wittmann

Jerome Faist
title: Microwatt level terahertz sources based on intra cavity difference frequency generation in mid infrared quantum cascade lasers
venue: 2008 Conference on Lasers and Electro Optics and 2008 Conference on Quantum Electronics and Laser Science
year: 2008