Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Log inSign up
Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Blog
Job Board
Q3AS

© 2026 Aqora Quantum S.A.S.

TermsPrivacyLegal Notice

Quantum 2.0 Conference and Exhibition

Two-Stage Quantum Frequency Conversion for SnV-resonant Photons to the Telecom C-Band

David Lindler, Tobias Bauer, Marlon Schäfer, Christoph Becher

Published Jan 1, 2023• 1 citation
Publisher

Abstract

We present a quantum frequency conversion scheme for photons resonat with SnV-centers in diamond to the telecom C-band, based on two-stage difference frequency generation in PPLN waveguides, to reduce noise at the target wavelength.
DOI
10.1364/quantum.2023.qw4a.1

Related papers

Bidirectional Two-Stage Quantum Frequency Conversion for SnV-resonant Photons to the Telecom C-Band

David Lindler, Tobias Bauer, Marlon Schäfer +1 more

We present a bidirectional quantum frequency conversion scheme for photons resonant with SnV-centers in diamond to the telecom C-band, based on two-stage difference frequency generation in PPLN waveguides.

Quantum 2.0 Conference and Exhibition•Jan 1, 2025•0 citations

Two-stage, low noise quantum frequency conversion of single photons from silicon-vacancy centers in diamond to the telecom C-band

Marlon Schäfer, Benjamin Kambs, Dennis Herrmann +2 more

The silicon-vacancy center in diamond holds great promise as a qubit for quantum communication networks. However, since the optical transitions are located within the visible red spectral region, quantum frequency conversion to low-loss telecommunication wavelengths becomes a necessity for its use in long-range, fiber-linked networks. This work presents a highly efficient, low-noise quantum frequency conversion device for photons emitted by a silicon-vacancy (SiV) center in diamond to the telecom C-band. By using a two-stage difference-frequency mixing scheme SPDC noise is circumvented and Raman noise is minimized, resulting in a very low noise rate of $10.4 \pm 0.7$ photons per second as well as an overall device efficiency of $35.6\, \%$. By converting single photons from SiV centers we demonstrate the preservation of photon statistics upon conversion.

arXiv:2307.11389•Jul 21, 2023•0 citations

Two‐Stage, Low Noise Quantum Frequency Conversion of Single Photons from Silicon‐Vacancy Centers in Diamond to the Telecom C‐Band

Marlon Schäfer, Benjamin Kambs, Dennis Herrmann +2 more

Abstract The silicon‐vacancy center in diamond holds great promise as a qubit for quantum communication networks. However, since the optical transitions are located within the visible red spectral region, quantum frequency conversion to low‐loss telecommunication wavelengths becomes a necessity for its use in long‐range, fiber‐linked networks. This work presents a highly efficient, low‐noise quantum frequency conversion device for photons emitted by a silicon‐vacancy (SiV) center in diamond to the telecom C‐band. By using a two‐stage difference‐frequency mixing scheme, spontaneous parametric down‐conversion (SPDC) noise is circumvented and Raman noise is minimized, resulting in a very low noise rate of photons per second as well as an overall device efficiency of 35.6%. By converting single photons from SiV centers, it demonstrates the preservation of photon statistics upon conversion.

Advanced Quantum Technologies•Sep 22, 2023•18 citations

Efficient Down-conversion of Single Photons for Quantum Communication

Jason S. Pelc, Carsten Langrock, Qi-Fa Zhang +1 more

We propose and demonstrate a system by which light from a diamond NV-center single photon source may be efficiently down-converted to the telecommunications band using difference frequency generation in a PPLN waveguide.

Advances in Optical Sciences Congress•Jan 1, 2009•3 citations

Quantum Frequency Conversion of Single Photons from a Tin-Vacancy Center in Diamond

Julia M. Brevoord, Jan Fabian Geus, Tim Turan +7 more

Diamond tin-vacancy (SnV) centers are promising candidates for building quantum network nodes. However, their native photon emission at 619 nm is incompatible with metropolitan-scale networks operating at low-loss telecom wavelengths. To address this, we demonstrate highly efficient, low-noise quantum frequency conversion (QFC) of 619 nm photons to the telecom S-band at 1480 nm. The conversion process combines 619 nm photons with 1064 nm pump light in an actively stabilized cavity containing a bulk monocrystalline potassium titanyl arsenate (KTA) crystal. We achieve an internal (external) conversion efficiency of (48 +/- 3)% ((28 +/- 2)%) and a noise photon rate per wavelength of 2.2 +/- 0.9 cts/s/pm, which is spectrally flat in the investigated frequency range of 40 GHz. Furthermore, we demonstrate that the efficiency remains above 80% of its maximum over a frequency range of 70 GHz. Finally, we generate a string of photons from a single waveguide-embedded SnV center using a train of excitation pulses and send these through the QFC. After the QFC, we observe a string of telecom photons displaying the SnV lifetime, confirming successful conversion. These results represent a critical step towards metropolitan-scale fiber-based quantum networks using SnV centers.

arXiv:2509.01661•Sep 1, 2025•1 citation

Quantum frequency conversion of single photons from a tin-vacancy center in diamond

Julia M. Brevoord, Jan Fabian Geus, Tim Turan +7 more

Diamond tin-vacancy (SnV) centers are promising candidates for building quantum network nodes. However, their native photon emission at 619 nm is incompatible with metropolitan-scale networks operating at low-loss telecom wavelengths. To address this, we demonstrate highly efficient, low-noise quantum frequency conversion (QFC) of 619 nm photons to the telecom S-band at 1480 nm. The conversion process combines 619 nm photons with 1064 nm pump light in an actively stabilized cavity containing a bulk monocrystalline potassium titanyl arsenate (KTA) crystal. We achieve an internal (external) conversion efficiency of (48 ± 3) % ((28 ± 2) %) and a noise photon rate per wavelength of (2.2 ± 0.9) cts/s/pm, which is spectrally flat in the investigated frequency range of 40 GHz. Furthermore, we demonstrate that the efficiency remains above 80% of its maximum over a frequency range of 70 GHz. Finally, we generate a string of photons from a single waveguide-embedded SnV − center using a train of excitation pulses and send these through the QFC. After the QFC, we observe telecom light displaying the SnV lifetime, confirming successful conversion. These results represent a critical step towards metropolitan-scale fiber-based quantum networks using SnV − centers.

Optica Quantum•Dec 10, 2025•3 citations
The silicon-vacancy center in diamond holds great promise as a qubit for quantum communication networks. However, since the optical transitions are located within the visible red spectral region, quantum frequency conversion to low-loss telecommunication wavelengths becomes a necessity for its use in long-range, fiber-linked networks. This work presents a highly efficient, low-noise quantum frequency conversion device for photons emitted by a silicon-vacancy (SiV) center in diamond to the telecom C-band. By using a two-stage difference-frequency mixing scheme SPDC noise is circumvented and Raman noise is minimized, resulting in a very low noise rate of 10.4±0.710.4 \pm 0.710.4±0.7 photons per second as well as an overall device efficiency of 35.6 %35.6\, \%35.6%. By converting single photons from SiV centers we demonstrate the preservation of photon statistics upon conversion.
Abstract The silicon‐vacancy center in diamond holds great promise as a qubit for quantum communication networks. However, since the optical transitions are located within the visible red spectral region, quantum frequency conversion to low‐loss telecommunication wavelengths becomes a necessity for its use in long‐range, fiber‐linked networks. This work presents a highly efficient, low‐noise quantum frequency conversion device for photons emitted by a silicon‐vacancy (SiV) center in diamond to the telecom C‐band. By using a two‐stage difference‐frequency mixing scheme, spontaneous parametric down‐conversion (SPDC) noise is circumvented and Raman noise is minimized, resulting in a very low noise rate of photons per second as well as an overall device efficiency of 35.6%. By converting single photons from SiV centers, it demonstrates the preservation of photon statistics upon conversion.
Diamond tin-vacancy (SnV) centers are promising candidates for building quantum network nodes. However, their native photon emission at 619 nm is incompatible with metropolitan-scale networks operating at low-loss telecom wavelengths. To address this, we demonstrate highly efficient, low-noise quantum frequency conversion (QFC) of 619 nm photons to the telecom S-band at 1480 nm. The conversion process combines 619 nm photons with 1064 nm pump light in an actively stabilized cavity containing a bulk monocrystalline potassium titanyl arsenate (KTA) crystal. We achieve an internal (external) conversion efficiency of (48 +/- 3)% ((28 +/- 2)%) and a noise photon rate per wavelength of 2.2 +/- 0.9 cts/s/pm, which is spectrally flat in the investigated frequency range of 40 GHz. Furthermore, we demonstrate that the efficiency remains above 80% of its maximum over a frequency range of 70 GHz. Finally, we generate a string of photons from a single waveguide-embedded SnV center using a train of excitation pulses and send these through the QFC. After the QFC, we observe a string of telecom photons displaying the SnV lifetime, confirming successful conversion. These results represent a critical step towards metropolitan-scale fiber-based quantum networks using SnV centers.
Diamond tin-vacancy (SnV) centers are promising candidates for building quantum network nodes. However, their native photon emission at 619 nm is incompatible with metropolitan-scale networks operating at low-loss telecom wavelengths. To address this, we demonstrate highly efficient, low-noise quantum frequency conversion (QFC) of 619 nm photons to the telecom S-band at 1480 nm. The conversion process combines 619 nm photons with 1064 nm pump light in an actively stabilized cavity containing a bulk monocrystalline potassium titanyl arsenate (KTA) crystal. We achieve an internal (external) conversion efficiency of (48 ± 3) % ((28 ± 2) %) and a noise photon rate per wavelength of (2.2 ± 0.9) cts/s/pm, which is spectrally flat in the investigated frequency range of 40 GHz. Furthermore, we demonstrate that the efficiency remains above 80% of its maximum over a frequency range of 70 GHz. Finally, we generate a string of photons from a single waveguide-embedded SnV − center using a train of excitation pulses and send these through the QFC. After the QFC, we observe telecom light displaying the SnV lifetime, confirming successful conversion. These results represent a critical step towards metropolitan-scale fiber-based quantum networks using SnV − centers.