國立高雄大學圖資館 |

Development of Thermally-Stable and Reflection-Insensitive Quantum Dot Lasers for LiDAR.

Record Type:	Electronic resources : Monograph/item
Title/Author:	Development of Thermally-Stable and Reflection-Insensitive Quantum Dot Lasers for LiDAR.
Author:	Arefn, Riazul.
Published:	Ann Arbor : ProQuest Dissertations & Theses, 2023
Description:	176 p.
Notes:	Source: Dissertations Abstracts International, Volume: 85-04, Section: B.
Notes:	Advisor: Arafn, Shamsul.
Contained By:	Dissertations Abstracts International85-04B.
Subject:	Nanotechnology.
Online resource:	http://pqdd.sinica.edu.tw/twdaoapp/servlet/advanced?query=30788395
ISBN:	9798380596442

Development of Thermally-Stable and Reflection-Insensitive Quantum Dot Lasers for LiDAR.
Arefn, Riazul.

Development of Thermally-Stable and Reflection-Insensitive Quantum Dot Lasers for LiDAR. - Ann Arbor : ProQuest Dissertations & Theses, 2023 - 176 p.

Source: Dissertations Abstracts International, Volume: 85-04, Section: B.

Thesis (Ph.D.)--The Ohio State University, 2023.

This item must not be sold to any third party vendors.

The objective of this thesis is to create highly efective light emitters for LiDAR technology by utilizing gain materials that are based on semiconductor quantum dots (QDs). The primary component of LiDAR technology is the light source, which is typically a laser. In order to function efectively under various conditions and with optimal efciency, the laser must meet specifc criteria: it should be safe for the eyes, provide high output power, exhibit thermal stability, and be insensitive to back-refections. QD materials possess advantageous properties such as three-dimensional carrier confnement and atom-like gain, resulting in discrete density of states. These properties contribute to an ultralow linewidth enhancement factor ‘α’, leading to improved thermal stability, reduced sensitivity to back-refection, narrow spectral linewidth, and low-chirp characteristics under modulation.This study focuses on the development of a light source using diode lasers for two specifc LiDAR wavelengths: 905 nm and 1.55 µm. The choice of these wavelengths is based on their respective advantages. The 905 nm wavelength has the lowest absorption in the atmosphere, making it an excellent option for topographic LiDARs used in navigation and environmental sensing. On the other hand, the 1.55 µm wavelength is considered eye-safe because it is blocked by retinal water and protects the cornea from potential damage. The 905 nm emitting QDs are based on the GaAs material platform, while the 1.55 µm wavelength utilizes InP-based materials. The work conducted in this thesis starts with material design and progresses to optimizing growth conditions to achieve high-density and uniform QD ensembles. Subsequently, these QDs are implemented into the epitaxial structure of diode lasers, which are then fabricated and characterized to ensure thermal stability and insensitivity to back-refection.The wavelength regime commonly referred to as the ‘Telecom band’ centered at 1.55 µm has well-established growth technology for QDs, exhibiting a remarkably low full-width at half maximum (FWHM) of 17 meV, which indicates a high level of uniformity. This research presents the development of QD laser diodes that achieves a moderately high output power exceeding 100 mW, demonstrating excellent thermal stability with wavelength coefcient of less than 0.4 nm/K in the temperature range of 0-80°C. Furthermore, the laser exhibits a high characteristic temperature (T0) of 100 K. A comprehensive comparison is conducted between the QD-based materials and similar materials based on quantum wells (QWs) in terms of their optoelectronic properties. The design and fabrication processes are optimized to produce diode lasers that operate in true single mode, making them suitable for practical applications.The wavelength of 905 nm is not widely explored in the QD research community. In this study, we investigated the growth of QDs on a novel InAlGaAs-based quaternary material system. Various growth conditions were employed to manipulate the morphology and composition of the QDs. Our research reveals a wide tuning range of 700 nm to 1.1 µm for the growth window of these QDs. The impact of ex-situ thermal annealing was extensively examined, and it was discovered that the material quality signifcantly improved with the application of annealing. Subsequently, the optimized materials were incorporated into the active region of diode lasers, and diagnostic lasers were fabricated and tested. The results from these experiments were used to further optimize and fne-tune the growth conditions of the materials to achieve the desired emission wavelength and superior optoelectronic performance. Additionally, new strategies were developed to create single-mode lasers. This work establishes a fundamental basis for selecting laser materials suitable for LiDAR technology applications.

ISBN: 9798380596442Subjects--Topical Terms:

193873
Nanotechnology.
Subjects--Index Terms:

Quantum dots

Development of Thermally-Stable and Reflection-Insensitive Quantum Dot Lasers for LiDAR.
LDR:05230nmm a2200433 4500 001 655874
005 20240414211954.5
006 m o d
007 cr#unu||||||||
008 240620s2023 ||||||||||||||||| ||eng d
020 $a 9798380596442
035 $a (MiAaPQ)AAI30788395
035 $a (MiAaPQ)OhioLINKosu1689920874057965
035 $a AAI30788395
040 $a MiAaPQ $c MiAaPQ
100 1 $a Arefn, Riazul. $3 967066
245 1 0 $a Development of Thermally-Stable and Reflection-Insensitive Quantum Dot Lasers for LiDAR.
260 1 $a Ann Arbor : $b ProQuest Dissertations & Theses, $c 2023
300 $a 176 p.
500 $a Source: Dissertations Abstracts International, Volume: 85-04, Section: B.
500 $a Advisor: Arafn, Shamsul.
502 $a Thesis (Ph.D.)--The Ohio State University, 2023.
506 $a This item must not be sold to any third party vendors.
520 $a The objective of this thesis is to create highly efective light emitters for LiDAR technology by utilizing gain materials that are based on semiconductor quantum dots (QDs). The primary component of LiDAR technology is the light source, which is typically a laser. In order to function efectively under various conditions and with optimal efciency, the laser must meet specifc criteria: it should be safe for the eyes, provide high output power, exhibit thermal stability, and be insensitive to back-refections. QD materials possess advantageous properties such as three-dimensional carrier confnement and atom-like gain, resulting in discrete density of states. These properties contribute to an ultralow linewidth enhancement factor ‘α’, leading to improved thermal stability, reduced sensitivity to back-refection, narrow spectral linewidth, and low-chirp characteristics under modulation.This study focuses on the development of a light source using diode lasers for two specifc LiDAR wavelengths: 905 nm and 1.55 µm. The choice of these wavelengths is based on their respective advantages. The 905 nm wavelength has the lowest absorption in the atmosphere, making it an excellent option for topographic LiDARs used in navigation and environmental sensing. On the other hand, the 1.55 µm wavelength is considered eye-safe because it is blocked by retinal water and protects the cornea from potential damage. The 905 nm emitting QDs are based on the GaAs material platform, while the 1.55 µm wavelength utilizes InP-based materials. The work conducted in this thesis starts with material design and progresses to optimizing growth conditions to achieve high-density and uniform QD ensembles. Subsequently, these QDs are implemented into the epitaxial structure of diode lasers, which are then fabricated and characterized to ensure thermal stability and insensitivity to back-refection.The wavelength regime commonly referred to as the ‘Telecom band’ centered at 1.55 µm has well-established growth technology for QDs, exhibiting a remarkably low full-width at half maximum (FWHM) of 17 meV, which indicates a high level of uniformity. This research presents the development of QD laser diodes that achieves a moderately high output power exceeding 100 mW, demonstrating excellent thermal stability with wavelength coefcient of less than 0.4 nm/K in the temperature range of 0-80°C. Furthermore, the laser exhibits a high characteristic temperature (T0) of 100 K. A comprehensive comparison is conducted between the QD-based materials and similar materials based on quantum wells (QWs) in terms of their optoelectronic properties. The design and fabrication processes are optimized to produce diode lasers that operate in true single mode, making them suitable for practical applications.The wavelength of 905 nm is not widely explored in the QD research community. In this study, we investigated the growth of QDs on a novel InAlGaAs-based quaternary material system. Various growth conditions were employed to manipulate the morphology and composition of the QDs. Our research reveals a wide tuning range of 700 nm to 1.1 µm for the growth window of these QDs. The impact of ex-situ thermal annealing was extensively examined, and it was discovered that the material quality signifcantly improved with the application of annealing. Subsequently, the optimized materials were incorporated into the active region of diode lasers, and diagnostic lasers were fabricated and tested. The results from these experiments were used to further optimize and fne-tune the growth conditions of the materials to achieve the desired emission wavelength and superior optoelectronic performance. Additionally, new strategies were developed to create single-mode lasers. This work establishes a fundamental basis for selecting laser materials suitable for LiDAR technology applications.
590 $a School code: 0168.
650 4 $a Nanotechnology. $3 193873
650 4 $a Nanoscience. $3 220425
650 4 $a Engineering. $3 210888
650 4 $a Electrical engineering. $3 454503
653 $a Quantum dots
653 $a Diode lasers
653 $a Epitaxy
653 $a Characteristic temperature
653 $a Threshold current
653 $a Rapid thermal annealing
690 $a 0652
690 $a 0565
690 $a 0544
690 $a 0537
710 2 $a The Ohio State University. $b Electrical and Computer Engineering. $3 531009
773 0 $t Dissertations Abstracts International $g 85-04B.
790 $a 0168
791 $a Ph.D.
792 $a 2023
793 $a English
856 4 0 $u http://pqdd.sinica.edu.tw/twdaoapp/servlet/advanced?query=30788395