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

Physical Review Letters

Observation of quantum frequency conversion

Jianming Huang, Prem Kumar

Published Apr 1, 1992• 273 citations
Publisher

Abstract

Quantum frequency conversion, a process with which an input beam of light can be converted into an output beam of a different frequency while preserving the quantum state, is experimentally demonstrated for the first time. Nonclassical intensity correlation (\ensuremath{\simeq}3 dB) between two beams at 1064 nm is used as the input quantum property. When the frequency of one of the beams is converted from 1064 to 532 nm, nonclassical intensity correlations (\ensuremath{\simeq}1.5 dB) appear between the up-converted beam and the remaining beam. Our measurements are in excellent agreement with the quantum theory of frequency conversion. The development of tunable sources of novel quantum light states seems possible.

DOI
10.1103/physrevlett.68.2153

Related papers

Observation of quantum frequency conversion

Jianming Huang, Prem Kumar

Quantum frequency conversion,1 a process with which one beam of light can be converted into another of a different frequency while preserving the quantum state, is experimentally demonstrated. An implementation of quantum frequency conversion requires that an input beam to a sum-frequency generator be completely up-converted. One needs to generate a quantum state (e.g., a squeezed state or a twin- beam state) at one frequency and then show that the properties of the same state appear at the up-converted frequency. We have chosen to use nonclassical intensity correlation of the twin beams as the input quantum property because large correlations can be easily obtained by pumping an optical parametric amplifier with a mode-locked and Q-switched laser.2 After one of the twin beams is up-converted, nonclassical intensity correlations appear between the up-converted beam and the remaining twin beam. In our experiment the 1064nm output signal beam of the parametric amplifier, possessing >3 dB nonclassical intensity correlation with the 1064nm output idler beam, is up-converted into a 532nm beam. The 532nm beam shows >2 dB nonclassical correlation with the 1064nm idler beam, demonstrating the quantum frequency conversion process.

Annual Meeting Optical Society of America•Jan 1, 1991•26 citations

Quantum frequency conversion of vacuum squeezed light to bright tunable blue squeezed light and higher-order spatial modes

Hugo Kerdoncuff, Jesper B. Christensen, Mikael Lassen

Quantum frequency conversion, the process of shifting the frequency of an optical quantum state while preserving quantum coherence, can be used to produce non-classical light at otherwise unapproachable wavelengths. We present experimental results based on highly efficient sum-frequency generation (SFG) between a vacuum squeezed state at 1064 nm and a tunable pump source at 850 nm $\pm$ 50 nm for the generation of bright squeezed light at 472~nm $\pm$ 4~nm, currently limited by the phase-matching of the used nonlinear crystal. We demonstrate that the SFG process conserves part of the quantum coherence as a 4.2($\pm0.2$)~dB 1064 nm vacuum squeezed state is converted to a 1.6($\pm$0.2)~dB tunable bright blue squeezed state. We furthermore demonstrate simultaneous frequency- and spatial-mode conversion of the 1064-nm vacuum squeezed state, and measure 1.1($\pm$0.2)~dB and 0.4($\pm$0.2)~dB of squeezing in the TEM$_{01}$ and TEM$_{02}$ modes, respectively. With further development, we foresee that the source may find use within fields such as sensing, metrology, spectroscopy, and imaging.

arXiv:2108.12140•Aug 27, 2021•0 citations

Quantum frequency conversion of vacuum squeezed light to bright tunable blue squeezed light and higher-order spatial modes

Hugo Kerdoncuff, Jesper B. Christensen, Mikael Lassen

Quantum frequency conversion, the process of shifting the frequency of an optical quantum state while preserving quantum coherence, can be used to produce non-classical light at otherwise unapproachable wavelengths. We present experimental results based on highly efficient sum-frequency generation (SFG) between a vacuum squeezed state at 1064 nm and a tunable pump source at 850 nm ± 50 nm for the generation of bright squeezed light at 472 nm ± 4 nm, currently limited by the phase-matching of the used nonlinear crystal. We demonstrate that the SFG process conserves part of the quantum coherence as a 4.2(±0.2) dB 1064 nm vacuum squeezed state is converted to a 1.6(±0.2) dB tunable bright blue squeezed state. We furthermore demonstrate simultaneous frequency- and spatial-mode conversion of the 1064-nm vacuum squeezed state, and measure 1.1(±0.2) dB and 0.4(±0.2) dB of squeezing in the TEM01 and TEM02 modes, respectively. With further development, we foresee that the source may find use within fields such as sensing, metrology, spectroscopy, and imaging.

Optics Express•Aug 25, 2021•16 citations

Quantum frequency conversion of vacuum squeezed light to bright tunable blue squeezed light

Hugo Kerdoncuff, Jesper B. Christensen, Mikael Lassen

Quantum frequency conversion, the process of shifting the frequency of an optical quantum state while preserving quantum coherence, can be used to produce non-classical light at otherwise unapproachable wavelengths. We present experimental results based on highly efficient sum-frequency generation (SFG) between a vacuum squeezed state at 1064 nm and a tunable pump source at 850 nm ± 50 nm for the generation of bright squeezed light at 472 nm ± 4 nm. We demonstrate that the SFG process conserves part of the quantum coherence as a 4.2(±0.2) dB 1064 nm vacuum squeezed state is converted to a 1.6(±0.2) dB tunable bright blue squeezed state.

Optical and Quantum Sensing and Precision Metrology II•Mar 8, 2023•0 citations

A photonic quantum interface for visible-to-telecommunication wavelength conversion

Takashi Yamamoto, Rikizo Ikuta, Masato Koashi +1 more

In our recent studies, we demonstrated a conversion of a visible photon at 780 nm to a 1522-nm photon by using difference frequency generation. Intensity correlation measurement on the converted light confirmed that the non-classical property of the input single photon is retained over the conversion process. We further performed a conversion of one half of an entangled photon pair and observed a highly entangled photon pair at 780-nm and 1522-nm, which shows that the quantum information is really transferred in the quantum interface.

IEEE Photonics Conference•Sep 1, 2012•0 citations

Frequency conversion of structured light

Fabian Steinlechner, Nathaniel Hermosa, Valerio Pruneri +1 more

Coherent frequency conversion of structured light, i.e. the ability to manipulate the carrier frequency of a wave front without distorting its spatial phase and intensity profile, provides the opportunity for numerous novel applications in photonic technology and fundamental science. In particular, frequency conversion of spatial modes carrying orbital angular momentum can be exploited in sub-wavelength resolution nano-optics and coherent imaging at a wavelength different from that used to illuminate an object. Moreover, coherent frequency conversion will be crucial for interfacing information stored in the high-dimensional spatial structure of single and entangled photons with various constituents of quantum networks. In this work, we demonstrate frequency conversion of structured light from the near infrared (803 nm) to the visible (527 nm). The conversion scheme is based on sum-frequency generation in a periodically poled lithium niobate crystal pumped with a 1540-nm Gaussian beam. We observe frequency-converted fields that exhibit a high degree of similarity with the input field and verify the coherence of the frequency-conversion process via mode projection measurements with a phase mask and a single-mode fiber. Our results demonstrate the suitability of exploiting the technique for applications in quantum information processing and coherent imaging.

Scientific Reports•Feb 15, 2016•41 citations
Quantum frequency conversion, a process with which an input beam of light can be converted into an output beam of a different frequency while preserving the quantum state, is experimentally demonstrated for the first time. Nonclassical intensity correlation (\ensuremath{\simeq}3 dB) between two beams at 1064 nm is used as the input quantum property. When the frequency of one of the beams is converted from 1064 to 532 nm, nonclassical intensity correlations (\ensuremath{\simeq}1.5 dB) appear between the up-converted beam and the remaining beam. Our measurements are in excellent agreement with the quantum theory of frequency conversion. The development of tunable sources of novel quantum light states seems possible.
Quantum frequency conversion,1 a process with which one beam of light can be converted into another of a different frequency while preserving the quantum state, is experimentally demonstrated. An implementation of quantum frequency conversion requires that an input beam to a sum-frequency generator be completely up-converted. One needs to generate a quantum state (e.g., a squeezed state or a twin- beam state) at one frequency and then show that the properties of the same state appear at the up-converted frequency. We have chosen to use nonclassical intensity correlation of the twin beams as the input quantum property because large correlations can be easily obtained by pumping an optical parametric amplifier with a mode-locked and Q-switched laser.2 After one of the twin beams is up-converted, nonclassical intensity correlations appear between the up-converted beam and the remaining twin beam. In our experiment the 1064nm output signal beam of the parametric amplifier, possessing >3 dB nonclassical intensity correlation with the 1064nm output idler beam, is up-converted into a 532nm beam. The 532nm beam shows >2 dB nonclassical correlation with the 1064nm idler beam, demonstrating the quantum frequency conversion process.
Quantum frequency conversion, the process of shifting the frequency of an optical quantum state while preserving quantum coherence, can be used to produce non-classical light at otherwise unapproachable wavelengths. We present experimental results based on highly efficient sum-frequency generation (SFG) between a vacuum squeezed state at 1064 nm and a tunable pump source at 850 nm ±\pm± 50 nm for the generation of bright squeezed light at 472~nm ±\pm± 4~nm, currently limited by the phase-matching of the used nonlinear crystal. We demonstrate that the SFG process conserves part of the quantum coherence as a 4.2(±0.2\pm0.2±0.2)~dB 1064 nm vacuum squeezed state is converted to a 1.6($\pm0.2) dBtunablebrightbluesqueezedstate.Wefurthermoredemonstratesimultaneousfrequency−andspatial−modeconversionofthe1064−nmvacuumsqueezedstate,andmeasure1.1(0.2)~dB tunable bright blue squeezed state. We furthermore demonstrate simultaneous frequency- and spatial-mode conversion of the 1064-nm vacuum squeezed state, and measure 1.1(0.2) dBtunablebrightbluesqueezedstate.Wefurthermoredemonstratesimultaneousfrequency−andspatial−modeconversionofthe1064−nmvacuumsqueezedstate,andmeasure1.1(\pm0.2) dBand0.4(0.2)~dB and 0.4(0.2) dBand0.4(\pm0.2) dBofsqueezingintheTEM0.2)~dB of squeezing in the TEM0.2) dBofsqueezingintheTEM_{01}$ and TEM02_{02}02​ modes, respectively. With further development, we foresee that the source may find use within fields such as sensing, metrology, spectroscopy, and imaging.
Quantum frequency conversion, the process of shifting the frequency of an optical quantum state while preserving quantum coherence, can be used to produce non-classical light at otherwise unapproachable wavelengths. We present experimental results based on highly efficient sum-frequency generation (SFG) between a vacuum squeezed state at 1064 nm and a tunable pump source at 850 nm ± 50 nm for the generation of bright squeezed light at 472 nm ± 4 nm, currently limited by the phase-matching of the used nonlinear crystal. We demonstrate that the SFG process conserves part of the quantum coherence as a 4.2(±0.2) dB 1064 nm vacuum squeezed state is converted to a 1.6(±0.2) dB tunable bright blue squeezed state. We furthermore demonstrate simultaneous frequency- and spatial-mode conversion of the 1064-nm vacuum squeezed state, and measure 1.1(±0.2) dB and 0.4(±0.2) dB of squeezing in the TEM01 and TEM02 modes, respectively. With further development, we foresee that the source may find use within fields such as sensing, metrology, spectroscopy, and imaging.
Quantum frequency conversion, the process of shifting the frequency of an optical quantum state while preserving quantum coherence, can be used to produce non-classical light at otherwise unapproachable wavelengths. We present experimental results based on highly efficient sum-frequency generation (SFG) between a vacuum squeezed state at 1064 nm and a tunable pump source at 850 nm ± 50 nm for the generation of bright squeezed light at 472 nm ± 4 nm. We demonstrate that the SFG process conserves part of the quantum coherence as a 4.2(±0.2) dB 1064 nm vacuum squeezed state is converted to a 1.6(±0.2) dB tunable bright blue squeezed state.
In our recent studies, we demonstrated a conversion of a visible photon at 780 nm to a 1522-nm photon by using difference frequency generation. Intensity correlation measurement on the converted light confirmed that the non-classical property of the input single photon is retained over the conversion process. We further performed a conversion of one half of an entangled photon pair and observed a highly entangled photon pair at 780-nm and 1522-nm, which shows that the quantum information is really transferred in the quantum interface.
Coherent frequency conversion of structured light, i.e. the ability to manipulate the carrier frequency of a wave front without distorting its spatial phase and intensity profile, provides the opportunity for numerous novel applications in photonic technology and fundamental science. In particular, frequency conversion of spatial modes carrying orbital angular momentum can be exploited in sub-wavelength resolution nano-optics and coherent imaging at a wavelength different from that used to illuminate an object. Moreover, coherent frequency conversion will be crucial for interfacing information stored in the high-dimensional spatial structure of single and entangled photons with various constituents of quantum networks. In this work, we demonstrate frequency conversion of structured light from the near infrared (803 nm) to the visible (527 nm). The conversion scheme is based on sum-frequency generation in a periodically poled lithium niobate crystal pumped with a 1540-nm Gaussian beam. We observe frequency-converted fields that exhibit a high degree of similarity with the input field and verify the coherence of the frequency-conversion process via mode projection measurements with a phase mask and a single-mode fiber. Our results demonstrate the suitability of exploiting the technique for applications in quantum information processing and coherent imaging.