Ignition of quantum cascade lasers in a state of oscillating electric field domains
(2018) In Physical Review A 98(2).- Abstract
Quantum cascade lasers (QCLs) are generally designed to avoid negative differential conductivity (NDC) in the vicinity of the operation point in order to prevent instabilities. We demonstrate that the threshold condition is possible under an inhomogeneous distribution of the electric field (domains) and leads to lasing at an operation point with a voltage bias normally attributed to the NDC region. For our example, a terahertz QCL operating up to the current maximum temperature of 199 K, the theoretical findings agree well with the experimental observations. In particular, we experimentally observe self-sustained oscillations with GHz frequency before and after threshold. These are attributed to traveling domains by our simulations.... (More)
Quantum cascade lasers (QCLs) are generally designed to avoid negative differential conductivity (NDC) in the vicinity of the operation point in order to prevent instabilities. We demonstrate that the threshold condition is possible under an inhomogeneous distribution of the electric field (domains) and leads to lasing at an operation point with a voltage bias normally attributed to the NDC region. For our example, a terahertz QCL operating up to the current maximum temperature of 199 K, the theoretical findings agree well with the experimental observations. In particular, we experimentally observe self-sustained oscillations with GHz frequency before and after threshold. These are attributed to traveling domains by our simulations. Overcoming the design paradigm to avoid NDC may allow for the further optimization of QCLs with less dissipation from stabilizing background currents.
(Less)
- author
- Winge, David O.
LU
; Dupont, Emmanuel
and Wacker, Andreas
LU
- organization
- publishing date
- 2018-08-20
- type
- Contribution to journal
- publication status
- published
- subject
- in
- Physical Review A
- volume
- 98
- issue
- 2
- article number
- 023834
- publisher
- American Physical Society
- external identifiers
-
- scopus:85052118455
- ISSN
- 2469-9926
- DOI
- 10.1103/PhysRevA.98.023834
- project
- Quantum Cascade Lasers beyond general paradigms
- language
- English
- LU publication?
- yes
- id
- 3eec8a8a-2126-4d22-85ff-2d1c01146b51
- date added to LUP
- 2018-09-26 14:46:28
- date last changed
- 2022-03-25 04:12:33
@article{3eec8a8a-2126-4d22-85ff-2d1c01146b51, abstract = {{<p>Quantum cascade lasers (QCLs) are generally designed to avoid negative differential conductivity (NDC) in the vicinity of the operation point in order to prevent instabilities. We demonstrate that the threshold condition is possible under an inhomogeneous distribution of the electric field (domains) and leads to lasing at an operation point with a voltage bias normally attributed to the NDC region. For our example, a terahertz QCL operating up to the current maximum temperature of 199 K, the theoretical findings agree well with the experimental observations. In particular, we experimentally observe self-sustained oscillations with GHz frequency before and after threshold. These are attributed to traveling domains by our simulations. Overcoming the design paradigm to avoid NDC may allow for the further optimization of QCLs with less dissipation from stabilizing background currents.</p>}}, author = {{Winge, David O. and Dupont, Emmanuel and Wacker, Andreas}}, issn = {{2469-9926}}, language = {{eng}}, month = {{08}}, number = {{2}}, publisher = {{American Physical Society}}, series = {{Physical Review A}}, title = {{Ignition of quantum cascade lasers in a state of oscillating electric field domains}}, url = {{https://lup.lub.lu.se/search/files/55496491/winge_PRA2018.pdf}}, doi = {{10.1103/PhysRevA.98.023834}}, volume = {{98}}, year = {{2018}}, }