Change search
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Carbon nanotube mode-locked optically-pumped semiconductor disk laser
KTH, School of Engineering Sciences (SCI), Applied Physics, Laser Physics.
KTH, School of Engineering Sciences (SCI), Applied Physics, Laser Physics.
Show others and affiliations
2013 (English)In: Optics Express, ISSN 1094-4087, E-ISSN 1094-4087, Vol. 21, no 15, 17806-17813 p.Article in journal (Refereed) Published
Abstract [en]

An optically pumped semiconductor disk laser was mode-locked for the first time by employing a single-walled carbon nanotube saturable absorber. Stable passive fundamental mode-locking was obtained at a repetition rate of 613 MHz with a pulse length of 1.23 ps. The mode-locked semiconductor disk laser in a compact geometry delivered a maximum average output power of 136 mW at 1074 nm.

Place, publisher, year, edition, pages
2013. Vol. 21, no 15, 17806-17813 p.
Keyword [en]
Solid-State Lasers, Saturable Absorber, High-Power, Locking, Pulses
National Category
Other Physics Topics
Identifiers
URN: urn:nbn:se:kth:diva-121987DOI: 10.1364/OE.21.017806ISI: 000322366300042Scopus ID: 2-s2.0-84880951935OAI: oai:DiVA.org:kth-121987DiVA: diva2:619924
Funder
Swedish Research Council
Note

QC 20130930. Updated from submitted to published.

Available from: 2013-05-07 Created: 2013-05-07 Last updated: 2017-12-06Bibliographically approved
In thesis
1. Compact solid-state lasers in the near-infrard and visible spectral range
Open this publication in new window or tab >>Compact solid-state lasers in the near-infrard and visible spectral range
2013 (English)Doctoral thesis, comprehensive summary (Other academic)
Abstract [en]

The subject of this thesis is the exploration of new concepts for compact solid-state lasers in the visible and near-infrared spectral range using new components such as volume Bragg gratings for wavelength stabilisation and wavelength tuning. Also single-walled carbon nanotubes for mode-locking and Q-switching of lasers have been studied.We have developed a new method for the tuning of solid-state lasers by replacing a dielectric mirror with a transversally chirped volume Bragg grating, which allows smooth wavelength tuning without additional elements inside the laser cavity. The result is a more compact laser, since the tuning mechanism and output coupler are incorporated in one component. Another benefit is an increased efficiency, since additional elements inside the cavity will always add to the total loss of the laser. This has been demonstrated for a broadband ytterbium laser around 1 µm and a single-longitudinal-mode Nd:YVO4 laser around 1.06 µm. A volume Bragg grating has also been used to construct an efficient, narrow-linewidth ytterbium fiber laser and the employment of a volume Bragg gratingas the pump mirror of a solid-state laser for frequency-doubling has been investigated. Both lasers represent a practical solution, eliminating the use of additional intracavity elements.

Second-harmonic generation is an efficient way to access the visible spectral range using diode-pumped solid-state lasers. However, these lasers can suffer from large amplitude fluctuations, which has been analyzed in more detail for an optically-pumped semiconductor disk-laser and a volume Bragg grating locked ytterbiumlaser. The control of those amplitude fluctuations is very important, since many applications like fluorescence microscopy require a laser with a constant output power and as little noise as possible.

In addition to this, we have demonstrated, that saturable absorbers based on quan-tum dots and carbon nanotubes can be used to mode-lock compact laser at a wavelength around 1.03 µm. Those lasers have many interesting applications incommunications, clock generation, metrology and life sciences.

Place, publisher, year, edition, pages
Stockholm: KTH Royal Institute of Technology, 2013. xii, 78, xi p.
Series
Trita-FYS, ISSN 0280-316X ; 2013:13
Keyword
volume Bragg gratings, single-longitudinal-mode laser, laser tuning, Q-switching, mode-locking, carbon nanotubes, semiconductor lasers, neodymium, ytterbium, nonlinear optics, KTP
National Category
Atom and Molecular Physics and Optics
Identifiers
urn:nbn:se:kth:diva-121976 (URN)978-91-7501-764-8 (ISBN)
Public defence
2013-05-30, FD5, Albanova, Roslagstullsbacken 21, Stockholm, 10:00 (English)
Opponent
Supervisors
Note

QC 20130507

Available from: 2013-05-07 Created: 2013-05-07 Last updated: 2015-03-30Bibliographically approved
2. Novel Technologies for Mode-Locking of Solid-State Lasers
Open this publication in new window or tab >>Novel Technologies for Mode-Locking of Solid-State Lasers
2013 (English)Doctoral thesis, comprehensive summary (Other academic)
Abstract [en]

The subject of this thesis is the investigation of novel technologies for mode-locking of diode-pumped, solid-state lasers. Novel saturable absorbers are used: quantum dots (QDs) and carbon nanotubes (CNTs), which both are low-dimensional nano-formations. In addition, mode-locking by cascaded nonlinearities is explored.

Absorber structures containing self-assembled InGaAs QDs are characterised in detail by pump-probe experiments, time-resolved photoluminescence spectroscopy, and measurement of the nonlinear reflectivity. The samples show sub-picosecond relaxation times of the reflectivity, modulation depths between 0.18% and 2.9%, as well as low saturation fluences on the order of 1–10μJ/cm2. The structures’ design parameters are related to their transient and nonlinear performance.

The characterised QD saturable absorbers are then used for mode-locking of diode-pumped, solid-state lasers, delivering picosecond pulses with optical spectra in the region of 1020–1040nm. In particular, a QD absorber with a saturation fluence of 4μJ/cm2 and a relaxation time <200fs is successfully employed for fundamental mode-locking of an Yb:KYW laser at a repetition rate of 1GHz. This laser emits pulses with a duration of 1.7ps at an output power of 339mW. Apart from this, an Yb-thin-disc laser is demonstrated, emitting pulses with a duration of 1.6ps at an output power of 13W, thereby showing, that the absorber withstands fluences of up to 2.4mJ/cm2 without being damaged.

An absorber with a linear loss of only 1% is obtained by embedding CNTs in a thin plastic film, coated onto a glass substrate. Using this absorber, mode-locking of an optically-pumped semiconductor disc-laser is achieved. The laser emits pulses with a duration of 1.12ps at a repetition rate of 613MHz and with an average output power of 136mW.

For cascaded mode-locking, a periodically-poled KTP crystal is placed inside a laser cavity and the two second-order nonlinearities from second-harmonic generation and back-conversion are used to emulate a third-order nonlinearity with an effective nonlinear refractive index of 2.33·10−17m2/W. For precise control of the nonlinearity, the laser’s spectrum is fixed to a wavelength of 1029.1nm by a volume Bragg grating. The laser emits pulses with a duration of 16ps at a repetition rate of 210MHz and with an output power of 690mW.

Place, publisher, year, edition, pages
Stockholm: KTH Royal Institute of Technology, 2013. xiii, 131 p.
Series
Trita-FYS, ISSN 0280-316X ; 2013:48
Keyword
laser, mode-locked laser, pulsed laser, quantum dot, carbon nanotube, nonlinear optics, saturable absorber, Kerr-lens mode-locking, ultra-fast laser, picosecond laser, pulsed laser, semiconductor saturable absorber
National Category
Atom and Molecular Physics and Optics
Identifiers
urn:nbn:se:kth:diva-131455 (URN)978-91-7501-840-9 (ISBN)
Public defence
2013-11-05, FA32, AlbaNova Universitetscentrum, Stockholm, 10:00 (English)
Opponent
Supervisors
Note

QC 20131016

Available from: 2013-10-16 Created: 2013-10-15 Last updated: 2013-10-16Bibliographically approved

Open Access in DiVA

No full text

Other links

Publisher's full textScopus

Authority records BETA

Laurell, FredrikPasiskevicius, Valdas

Search in DiVA

By author/editor
Seger, KaiMeiser, NielsRotermund, FabianLaurell, FredrikPasiskevicius, Valdas
By organisation
Laser Physics
In the same journal
Optics Express
Other Physics Topics

Search outside of DiVA

GoogleGoogle Scholar

doi
urn-nbn

Altmetric score

doi
urn-nbn
Total: 167 hits
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf