Show/Hide Menu
Hide/Show Apps
Logout
Türkçe
Türkçe
Search
Search
Login
Login
OpenMETU
OpenMETU
About
About
Open Science Policy
Open Science Policy
Open Access Guideline
Open Access Guideline
Postgraduate Thesis Guideline
Postgraduate Thesis Guideline
Communities & Collections
Communities & Collections
Help
Help
Frequently Asked Questions
Frequently Asked Questions
Guides
Guides
Thesis submission
Thesis submission
MS without thesis term project submission
MS without thesis term project submission
Publication submission with DOI
Publication submission with DOI
Publication submission
Publication submission
Supporting Information
Supporting Information
General Information
General Information
Copyright, Embargo and License
Copyright, Embargo and License
Contact us
Contact us
Thermal characterisation of quantum cascade lasers with Fabry Perot modes
Download
index.pdf
Date
2018-04-26
Author
Gundogdu, Sinan
Pisheh, Hadi Sedaghat
Demir, Abdullah
Guenoven, Mete
AYDINLI, ATİLLA
Sirtori, Carlo
Metadata
Show full item record
This work is licensed under a
Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License
.
Item Usage Stats
266
views
0
downloads
Cite This
Quantum cascade lasers are coherent light sources that rely on intrersubband transition in periodic semiconductor quantum well structures. They operate at frequencies from mid-infrared to terahertz. In cases of long wavelength and typical low thermal conductivity of the active region, temperature rise in the active region during operation is a major concern. Thermal conductivity of QCL epi-layers differ significantly from the values of bulk semiconductors and measurement of the thermal conductivity of epi-layers is critical for design. It is well known that Fabry-Perot spectra of QCL cavities exhibit fine amplitude oscillations with frequency and can be used for real time in-situ temperature measurement. Phase of the modulation depends on the group refractive index of the cavity, which depends on the cavity temperature. We fabricated QCL devices with from 12, to 24 um mesa widths and 2mm cavity length and and measured high resolution, high speed time resolved spectra using a FTIR spectrometer in step scan mode in a liquid nitrogen cooled, temperature controlled dewar. We used the time resolved spectra of QCLs to measure average temperature of the active region of the laser as a function of time. We examined the effect of pulse width and duty cycle on laser heating. We measured the temperature derivative of group refractive index of the cavity. Building a numerical model, we estimated the thermal conductivity of active region and calculated the heating of the QCL active region in pulsed mode for various waveguide widths.
Subject Keywords
Quantum cascade lasers
,
Thermal conductivity
URI
https://hdl.handle.net/11511/68295
DOI
https://doi.org/10.1117/12.2311651
Conference Name
Conference on Semiconductor Lasers and Laser Dynamics VIII
Collections
Department of Physics, Conference / Seminar
Suggestions
OpenMETU
Core
Time resolved Fabry-Perot measurements of cavity temperature in pulsed QCLs
Gundogdu, S.; Pisheh, H. S.; Demir, A.; Gunoven, M.; Aydinli, A.; Sirtori, C. (The Optical Society, 2018-3-5)
Temperature rise during operation is a central concern of semiconductor lasers and especially difficult to measure during a pulsed operation. We present a technique for in situ time-resolved temperature measurement of quantum cascade lasers operating in a pulsed mode at similar to 9.25 mu m emission wavelength. Using a step-scan approach with 5 ns resolution, we measure the temporal evolution of the spectral density, observing longitudinal Fabry-Perot modes that correspond to different transverse modes. Con...
Bioactive surface design based on conducting polymers and applications to biosensors
Erdem, Rengin; Özen, Can; Yağcı Acar, Havva Funda; Department of Biotechnology (2012)
Quantum dots are fluorescent semiconductor nanocrystals that have unique optical properties such as high quantum yield and photostability. These nanoparticles are superior to organic dyes and fluorescent proteins in many aspects and therefore show great potential for both in vivo and in vitro imaging and drug delivery applications. However, cytototoxicity is still one of the major problems associated with their biological applications. The aim of this study is in vitro characterization and assessment of bio...
Nonlinear optical properties of semiconductor heterostructures
Yıldırım, Hasan; Tomak, Mehmet; Department of Physics (2006)
The nonlinear optical properties of semiconductor heterostructures, such as GaAsAl/GaAs alloys, are studied with analytic and numerical methods on the basis of quantum mechanics. Particularly, second and third-order nonlinear optical properties of quantum wells described by the various types of confining potentials are considered within the density matrix formalism. We consider a Pöschl-Teller type potential which has been rarely considered in this area. It has a tunable asymmetry parameter, making it a goo...
Energy spectrum of a 2D Dirac oscillator in the presence of a constant magnetic field and an antidot potential
Akçay, Hüseyin; Sever, Ramazan (2016-07-04)
We investigate the energy spectrum and the corresponding eigenfunctions of a 2D Dirac oscillator confined by an antidot potential in the presence of a magnetic field and Aharonov-Bohm flux field. Analytical solutions are obtained and compared with the results of the Schrodinger equation found in the literature. Further, the dependence of the spectrum on the magnetic quantum number and on the repulsive potential is discussed.
Exciton related nonlinear optical properties of a spherical quantum dot
Aksahin, E.; Unal, V. Ustoglu; Tomak, Mehmet (2015-11-01)
The nonlinear optical properties of an exciton in a spherical quantum dot (QD) is studied analytically. The nonlinear optical coefficients are calculated within the density matrix formalism. The electronic problem is solved within the effective mass approximation. The contributions from the competing effects of the confinement, the Coulomb interaction, and the applied electric field are calculated and compared with each other. We have made no assumptions about the strength of the confinement. We concentrate...
Citation Formats
IEEE
ACM
APA
CHICAGO
MLA
BibTeX
S. Gundogdu, H. S. Pisheh, A. Demir, M. Guenoven, A. AYDINLI, and C. Sirtori, “Thermal characterisation of quantum cascade lasers with Fabry Perot modes,” Strasbourg, France, 2018, vol. 10682, p. 0, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/68295.