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
Fabrication of submicrometer quasi-phase-matched devices in KTP and RKTP [Invited]
KTH, School of Engineering Sciences (SCI), Applied Physics, Laser Physics.
KTH, School of Engineering Sciences (SCI), Applied Physics, Laser Physics.
KTH, School of Engineering Sciences (SCI), Applied Physics, Laser Physics.ORCID iD: 0000-0002-2508-391X
KTH, School of Engineering Sciences (SCI), Applied Physics, Laser Physics.ORCID iD: 0000-0001-7688-1367
Show others and affiliations
2011 (English)In: Optical Materials Express, ISSN 2159-3930, Vol. 1, no 7, 1319-1325 p.Article in journal (Refereed) Published
Abstract [en]

We review the techniques used for fabrication of bulk submicrometer ferroelectric domain gratings in KTiOPO4 (KTP) and demonstrate that bulk Rb-doped KTiOPO4 (RKTP) is an excellent candidate for implementation of dense domain gratings. Compared to KTP, RKTP presents predominant domain propagation along the polar c-direction, substantially reduced lateral domain broadening, and higher poling yield. As a result we obtain homogeneous sub-μm periodic poling of RKTP with a period of 690 nm in 1 mm thick samples.

Place, publisher, year, edition, pages
Optical Society of America, 2011. Vol. 1, no 7, 1319-1325 p.
Keyword [en]
Ferroelectrics, nonlinear optics, parametric processes
National Category
Atom and Molecular Physics and Optics Other Materials Engineering
Identifiers
URN: urn:nbn:se:kth:diva-51093ISI: 000299049200019Scopus ID: 2-s2.0-80755172823OAI: oai:DiVA.org:kth-51093DiVA: diva2:463379
Funder
Swedish Research Council
Note
QC 20111209Available from: 2011-12-09 Created: 2011-12-09 Last updated: 2015-03-30Bibliographically approved
In thesis
1. Nonlinear response in engineered optical materials
Open this publication in new window or tab >>Nonlinear response in engineered optical materials
2012 (English)Doctoral thesis, comprehensive summary (Other academic)
Abstract [en]

Material and structure engineering are increasingly employed in active optical media,in this context defined as media capable of providing laser or/and optical parametric gain. For laser materials, the main aim of the engineering is to tailor the absorption and emission cross sections in order to optimise the laser performance. At the same time, the engineering also results in a collateral modification of the material’s nonlinear response. In the first part of this work, the nonlinear index of refraction is characterised for two crystallographic forms of laser-ion doped and undoped double-tungstate crystals. These laser crystals have broad gain bandwidths, in particular when doped with Yb3+. As shown in this work, the crystals also have large Kerr nonlinearities, where the values vary significantly for different chemical compositions of the crystals. The combination of a broad gain bandwidthand a high Kerr nonlinearity makes the laser-ion doped double tungstates excellent candidates to employ for the generation of ultrashort laser pulses by Kerr-lens modelocking. The second part of the work relates to the applications of engineered second-order nonlinear media, which here in particular are periodically-poled KTiOPO4 crystals. Periodic structure engineering of second-order nonlinear crystals on a submicrometre scale opens up for the realisation of novel nonlinear devices. By the use of quasi-phase matching in these structures, it is possible to efficiently downconvert a pump wave into two counterpropagating parametric waves, which leads to a device called a mirrorless optical parametric oscillator. The nonlinear response in these engineered submicrometre structures is such that the parametric wave that propagates in the opposite direction of the pump automatically has a narrow bandwidth, whereas the parametric wave that propagates with the pump essentially is a frequency-shifted replica of the pump wave. The unusual spectral properties andthe tunabilities of mirrorless optical parametric oscillators are investigated.

Place, publisher, year, edition, pages
Stockholm: KTH Royal Institute of Technology, 2012. xii, 98 p.
Series
Trita-FYS, ISSN 0280-316X ; 2012:13
Keyword
nonlinear optics, nonlinear index of refraction, double tungstates, periodic poling, KTiOPO4, quasi-phase matching, parametric down-conversion, mirrorless optical parametric oscillators
National Category
Atom and Molecular Physics and Optics
Identifiers
urn:nbn:se:kth:diva-92221 (URN)978-91-7501-295-7 (ISBN)
Public defence
2012-04-27, FD5, Albanova, Roslagstullsbacke 21, KTH, Stockholm, 10:00 (English)
Opponent
Supervisors
Note
QC 20120330Available from: 2012-03-30 Created: 2012-03-29 Last updated: 2012-03-30Bibliographically approved
2. QPM Devices in KTA and RKTP
Open this publication in new window or tab >>QPM Devices in KTA and RKTP
2014 (English)Doctoral thesis, comprehensive summary (Other academic)
Abstract [en]

Even though KTiOPO4 (KTP) is considered to be one of the best nonlinear materials for quasi phase matched (QPM) frequency conversion in the visible and the near-infrared spectral regions, its use is often limited by poor material homogeneity, high ionic conductivity, a considerable linear absorption and photochromatic damage. On the other hand, the improved material homogeneity and the lower ionic conductivity of bulk Rb-doped KTP (RKTP) make this material an ideal alternative for fabrication of fine-pitch QPM gratings, while the arsenate isomorph KTiOAsO4 (KTA) promises a better performance in the green spectral region and adds the advantage of a wider transparency window in the infrared. Unfortunately, the available studies on these materials are limited and unable to answer the question whether RKTP and KTA are feasible alternatives to KTP in terms of periodic poling and optical performance. The optical performance of the QPM devices depends on the periodic poling quality, therefore, a detailed comprehension of domain-grating formation in the KTP isomorphs is highly desired. The goals of this thesis were to gain a better understanding of the periodic poling process in the KTP isomorphs, in order to study the specifics of ferroelectric domain engineering in KTA and RKTP, and to evaluate the optical performance of these isomorphs. Fine-pitch periodically poled structures were engineered both in KTA and RKTP crystals. It was demonstrated that QPM gratings with excellent quality and with periods as short as 8.49 μm can be fabricated in KTA crystals. Comparative transmission studies have shown that periodically poled KTA (PPKTA) crystals can be superior to KTP for QPM second harmonic generation in the visible spectral region due to lower linear absorption. It was also demonstrated that RKTP is a superior alternative to KTP for high-quality QPM grating fabrication. A consistent room-temperature periodic poling of 5 mm thick RKTP crystals with a period of 38.86 μm has been achieved. The obtained large aperture periodically poled RKTP (PPRKTP) crystals showed an outstanding QPM grating uniformity and excellent optical performance in optical parametric oscillator (OPO) applications. Moreover, it was shown that RKTP is less susceptible to blue-induced infrared absorption than KTP. Finally, a novel and a relatively simple method for self-assembling quasi-periodic sub-μm scale ferroelectric domain structure in RKTP crystals has been presented. It was shown that, after treatment in aqueous KOH/KNO3 solution, periodic poling of RKTP with planar electrodes resulted in one-dimensional ferroelectric domain structure with an average periodicity of 650±200 nm, extending over the whole 1 mm thick crystal. Such self-assembled structures in RKTP were used to demonstrate 5th order non-collinear QPM backward second harmonic generation.

Place, publisher, year, edition, pages
KTH Royal Institute of Technology, 2014. xiv, 98 p.
Series
TRITA-FYS, ISSN 0280-316X ; 2013:71
Keyword
QPM, periodic poling, KTP
National Category
Other Materials Engineering Other Physics Topics
Identifiers
urn:nbn:se:kth:diva-139475 (URN)978-91-7501-974-1 (ISBN)
Public defence
2014-01-31, sal FB52, AlbaNova Universitetscentrum, Roslagstullsbacken 21, Stockholm, 10:00 (English)
Opponent
Supervisors
Note

QC 20140114

Available from: 2014-01-14 Created: 2014-01-13 Last updated: 2014-01-14Bibliographically approved

Open Access in DiVA

No full text

Scopus

Authority records BETA

Pasiskevicius, ValdasLaurell, FredrikFokine, MichaelCanalias, Carlota

Search in DiVA

By author/editor
Zukauskas, AndriusStrömqvist, GustavPasiskevicius, ValdasLaurell, FredrikFokine, MichaelCanalias, Carlota
By organisation
Laser Physics
Atom and Molecular Physics and OpticsOther Materials Engineering

Search outside of DiVA

GoogleGoogle Scholar

urn-nbn

Altmetric score

urn-nbn
Total: 124 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