---
_id: '66939'
abstract:
- lang: eng
  text: "Many quantum optical applications in spectroscopy, communication and signal
    analysis rely on spectrally-engineered nonlinear optical interactions to target
    specific wavelengths or bandwidth. Here, in an established material platform like
    lithium niobate the achievable wavelength and bandwidth combinations are usually
    limited by the material’s dispersion and its birefringence. In this regard, mixed
    crystals of lithium niobate tantalate (LNT) promise a novel material platform,
    because they allow tuning the birefringence, which is central for type II phase
    matching devices. Crucially, LNT offers crystal  compositions without any birefringence,
    which still retain their second-order optical nonlinearity. Despite recent progress
    in the growth and fabrication of LNT, so far no works have investigated the unique
    properties of LNT for use in electro-optics, nonlinear or quantum optics. In this
    study, we explore nonlinear optical devices based on LNT for broad- and narrowband
    nonlinear optical interactions based on recently measured Sellmeier coefficients.
    Most interestingly, we find that compositions without birefringence allow the
    design of broadband, degenerate type II phase matching sources spanning the whole
    near- to mid-infrared range by only changing the poling period and pump wavelength.
    Such devices are not easily realizable in pure lithium niobate or lithium tantalate.
    This could potentially allow for\tmore flexible light sources and nonlinear devices
    in quantum metrology, quantum spectroscopy and quantum communication."
article_number: '2668'
article_type: original
author:
- first_name: Franz
  full_name: Roeder, Franz
  id: '88149'
  last_name: Roeder
- first_name: Michael
  full_name: Rüsing, Michael
  id: '22501'
  last_name: Rüsing
  orcid: 0000-0003-4682-4577
- first_name: Tobias
  full_name: Hehemann, Tobias
  last_name: Hehemann
- first_name: Abira
  full_name: Gnanavel, Abira
  id: '81424'
  last_name: Gnanavel
- first_name: Christof
  full_name: Eigner, Christof
  id: '13244'
  last_name: Eigner
  orcid: https://orcid.org/0000-0002-5693-3083
- first_name: Benjamin
  full_name: Brecht, Benjamin
  id: '27150'
  last_name: Brecht
  orcid: '0000-0003-4140-0556 '
- first_name: Mirco
  full_name: Imlau, Mirco
  last_name: Imlau
- first_name: Christine
  full_name: Silberhorn, Christine
  id: '26263'
  last_name: Silberhorn
citation:
  ama: 'Roeder F, Rüsing M, Hehemann T, et al. Lithium niobate tantalate mixed crystals:
    a versatile platform for nonlinear quantum processes. <i>Optical Materials Express</i>.
    2026;16(8). doi:<a href="https://doi.org/10.1364/ome.592892">10.1364/ome.592892</a>'
  apa: 'Roeder, F., Rüsing, M., Hehemann, T., Gnanavel, A., Eigner, C., Brecht, B.,
    Imlau, M., &#38; Silberhorn, C. (2026). Lithium niobate tantalate mixed crystals:
    a versatile platform for nonlinear quantum processes. <i>Optical Materials Express</i>,
    <i>16</i>(8), Article 2668. <a href="https://doi.org/10.1364/ome.592892">https://doi.org/10.1364/ome.592892</a>'
  bibtex: '@article{Roeder_Rüsing_Hehemann_Gnanavel_Eigner_Brecht_Imlau_Silberhorn_2026,
    title={Lithium niobate tantalate mixed crystals: a versatile platform for nonlinear
    quantum processes}, volume={16}, DOI={<a href="https://doi.org/10.1364/ome.592892">10.1364/ome.592892</a>},
    number={82668}, journal={Optical Materials Express}, publisher={Optica Publishing
    Group}, author={Roeder, Franz and Rüsing, Michael and Hehemann, Tobias and Gnanavel,
    Abira and Eigner, Christof and Brecht, Benjamin and Imlau, Mirco and Silberhorn,
    Christine}, year={2026} }'
  chicago: 'Roeder, Franz, Michael Rüsing, Tobias Hehemann, Abira Gnanavel, Christof
    Eigner, Benjamin Brecht, Mirco Imlau, and Christine Silberhorn. “Lithium Niobate
    Tantalate Mixed Crystals: A Versatile Platform for Nonlinear Quantum Processes.”
    <i>Optical Materials Express</i> 16, no. 8 (2026). <a href="https://doi.org/10.1364/ome.592892">https://doi.org/10.1364/ome.592892</a>.'
  ieee: 'F. Roeder <i>et al.</i>, “Lithium niobate tantalate mixed crystals: a versatile
    platform for nonlinear quantum processes,” <i>Optical Materials Express</i>, vol.
    16, no. 8, Art. no. 2668, 2026, doi: <a href="https://doi.org/10.1364/ome.592892">10.1364/ome.592892</a>.'
  mla: 'Roeder, Franz, et al. “Lithium Niobate Tantalate Mixed Crystals: A Versatile
    Platform for Nonlinear Quantum Processes.” <i>Optical Materials Express</i>, vol.
    16, no. 8, 2668, Optica Publishing Group, 2026, doi:<a href="https://doi.org/10.1364/ome.592892">10.1364/ome.592892</a>.'
  short: F. Roeder, M. Rüsing, T. Hehemann, A. Gnanavel, C. Eigner, B. Brecht, M.
    Imlau, C. Silberhorn, Optical Materials Express 16 (2026).
date_created: 2026-09-02T11:53:45Z
date_updated: 2026-09-02T13:35:22Z
department:
- _id: '288'
- _id: '623'
- _id: '15'
doi: 10.1364/ome.592892
funded_apc: '1'
intvolume: '        16'
issue: '8'
language:
- iso: eng
main_file_link:
- open_access: '1'
  url: https://doi.org/10.1364/OME.592892
oa: '1'
publication: Optical Materials Express
publication_identifier:
  issn:
  - 2159-3930
publication_status: published
publisher: Optica Publishing Group
quality_controlled: '1'
status: public
title: 'Lithium niobate tantalate mixed crystals: a versatile platform for nonlinear
  quantum processes'
type: journal_article
user_id: '22501'
volume: 16
year: '2026'
...
---
_id: '57862'
abstract:
- lang: eng
  text: The latest applications in ultrafast quantum metrology require bright, broadband
    bi-photon sources with one of the photons in the mid-infrared and the other in
    the visible to near infrared. However, existing sources based on bulk crystals
    are limited in brightness due to the short interaction length and only allow for
    limited dispersion engineering. Here, we present an integrated PDC source based
    on a Ti:LiNbO3 waveguide that generates broadband bi-photons with central wavelengths
    at 860 nm and 2800 nm. Their spectral bandwidth exceeds 25 THz and is achieved
    by simultaneous matching of the group velocities (GVs) and cancellation of GV
    dispersion for the signal and idler field. We provide an intuitive understanding
    of the process by studying our source’s behavior at different temperatures and
    pump wavelengths, which agrees well with simulations.
article_number: '123025'
article_type: original
author:
- first_name: Franz
  full_name: Roeder, Franz
  id: '88149'
  last_name: Roeder
- first_name: Abira
  full_name: Gnanavel, Abira
  id: '81424'
  last_name: Gnanavel
- first_name: René
  full_name: Pollmann, René
  id: '78890'
  last_name: Pollmann
- first_name: Olga
  full_name: Brecht, Olga
  last_name: Brecht
- first_name: Michael
  full_name: Stefszky, Michael
  id: '42777'
  last_name: Stefszky
- first_name: Laura
  full_name: Padberg, Laura
  id: '40300'
  last_name: Padberg
- first_name: Christof
  full_name: Eigner, Christof
  id: '13244'
  last_name: Eigner
  orcid: https://orcid.org/0000-0002-5693-3083
- first_name: Christine
  full_name: Silberhorn, Christine
  id: '26263'
  last_name: Silberhorn
- first_name: Benjamin
  full_name: Brecht, Benjamin
  id: '27150'
  last_name: Brecht
  orcid: '0000-0003-4140-0556 '
citation:
  ama: Roeder F, Gnanavel A, Pollmann R, et al. Ultra-broadband non-degenerate guided-wave
    bi-photon source in the near and mid-infrared. <i>New Journal of Physics</i>.
    2024;26(12). doi:<a href="https://doi.org/10.1088/1367-2630/ad9f98">10.1088/1367-2630/ad9f98</a>
  apa: Roeder, F., Gnanavel, A., Pollmann, R., Brecht, O., Stefszky, M., Padberg,
    L., Eigner, C., Silberhorn, C., &#38; Brecht, B. (2024). Ultra-broadband non-degenerate
    guided-wave bi-photon source in the near and mid-infrared. <i>New Journal of Physics</i>,
    <i>26</i>(12), Article 123025. <a href="https://doi.org/10.1088/1367-2630/ad9f98">https://doi.org/10.1088/1367-2630/ad9f98</a>
  bibtex: '@article{Roeder_Gnanavel_Pollmann_Brecht_Stefszky_Padberg_Eigner_Silberhorn_Brecht_2024,
    title={Ultra-broadband non-degenerate guided-wave bi-photon source in the near
    and mid-infrared}, volume={26}, DOI={<a href="https://doi.org/10.1088/1367-2630/ad9f98">10.1088/1367-2630/ad9f98</a>},
    number={12123025}, journal={New Journal of Physics}, publisher={IOP Publishing},
    author={Roeder, Franz and Gnanavel, Abira and Pollmann, René and Brecht, Olga
    and Stefszky, Michael and Padberg, Laura and Eigner, Christof and Silberhorn,
    Christine and Brecht, Benjamin}, year={2024} }'
  chicago: Roeder, Franz, Abira Gnanavel, René Pollmann, Olga Brecht, Michael Stefszky,
    Laura Padberg, Christof Eigner, Christine Silberhorn, and Benjamin Brecht. “Ultra-Broadband
    Non-Degenerate Guided-Wave Bi-Photon Source in the near and Mid-Infrared.” <i>New
    Journal of Physics</i> 26, no. 12 (2024). <a href="https://doi.org/10.1088/1367-2630/ad9f98">https://doi.org/10.1088/1367-2630/ad9f98</a>.
  ieee: 'F. Roeder <i>et al.</i>, “Ultra-broadband non-degenerate guided-wave bi-photon
    source in the near and mid-infrared,” <i>New Journal of Physics</i>, vol. 26,
    no. 12, Art. no. 123025, 2024, doi: <a href="https://doi.org/10.1088/1367-2630/ad9f98">10.1088/1367-2630/ad9f98</a>.'
  mla: Roeder, Franz, et al. “Ultra-Broadband Non-Degenerate Guided-Wave Bi-Photon
    Source in the near and Mid-Infrared.” <i>New Journal of Physics</i>, vol. 26,
    no. 12, 123025, IOP Publishing, 2024, doi:<a href="https://doi.org/10.1088/1367-2630/ad9f98">10.1088/1367-2630/ad9f98</a>.
  short: F. Roeder, A. Gnanavel, R. Pollmann, O. Brecht, M. Stefszky, L. Padberg,
    C. Eigner, C. Silberhorn, B. Brecht, New Journal of Physics 26 (2024).
date_created: 2024-12-27T19:01:14Z
date_updated: 2026-09-02T14:54:23Z
department:
- _id: '288'
- _id: '623'
- _id: '15'
doi: 10.1088/1367-2630/ad9f98
intvolume: '        26'
issue: '12'
language:
- iso: eng
project:
- _id: '571'
  name: 'MIRAQLS: MIRAQLS: Mid-infrared Quantum Technology for Sensing'
- _id: '190'
  name: 'E2TPA: Exploiting Entangled Two-Photon Absorption'
publication: New Journal of Physics
publication_identifier:
  issn:
  - 1367-2630
publication_status: published
publisher: IOP Publishing
status: public
title: Ultra-broadband non-degenerate guided-wave bi-photon source in the near and
  mid-infrared
type: journal_article
user_id: '13244'
volume: 26
year: '2024'
...