Kundu, I orcid.org/0000-0002-3564-1903, Dean, P orcid.org/0000-0002-3950-4359, Valavanis, A orcid.org/0000-0001-5565-0463 et al. (5 more authors) (2014) Discrete Vernier tuning in terahertz quantum cascade lasers using coupled cavities. Optics Express, 22 (13). pp. 16595-16605. ISSN 1094-4087
Abstract
Discrete Vernier frequency tuning of terahertz quantum cascade lasers is demonstrated using a device comprising a two-section coupled-cavity. The two sections are separated by a narrow air gap, which is milled after device packaging using a focused ion beam. One section of the device (the lasing section) is electrically biased above threshold using a short current pulse, while the other section (the tuning section) is biased below threshold with a wider current pulse to achieve controlled localized electrical heating. The resulting thermally-induced shift in the longitudinal cavity modes of the tuning section is engineered to produce either a controllable blue shift or red shift of the emission frequency. This discrete Vernier frequency tuning far exceeds the tuning achievable from standard ridge lasers, and does not lead to any corresponding change in emitted power. Discrete tuning was observed over bandwidths of 50 and 85 GHz in a pair of devices, each using different design schemes. Interchanging the lasing and tuning sections of the same devices yielded red shifts of 20 and 30 GHz, respectively.
Metadata
Item Type: | Article |
---|---|
Authors/Creators: |
|
Copyright, Publisher and Additional Information: | (c) 2014, Optical Society of America. This paper was published in Optics Express and is made available as an electronic reprint with the permission of OSA. The paper can be found at the following URL on the OSA website: http://dx.doi.org/10.1364/OE.22.016595. Systematic or multiple reproduction or distribution to multiple locations via electronic or other means is prohibited and is subject to penalties under law. |
Keywords: | Semiconductor lasers; quantum cascade; lasers; tunable |
Dates: |
|
Institution: | The University of Leeds |
Academic Units: | The University of Leeds > Faculty of Engineering & Physical Sciences (Leeds) > School of Electronic & Electrical Engineering (Leeds) > Pollard Institute (Leeds) |
Depositing User: | Symplectic Publications |
Date Deposited: | 03 Jul 2014 08:38 |
Last Modified: | 25 Feb 2019 11:34 |
Published Version: | http://dx.doi.org/10.1364/OE.22.016595 |
Status: | Published |
Publisher: | Optical Society of America |
Identification Number: | 10.1364/OE.22.016595 |
Open Archives Initiative ID (OAI ID): | oai:eprints.whiterose.ac.uk:79584 |