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

Optics Letters

Increased efficiency for sum-frequency generation for broadband input fields

Czesław Radzewicz, Jerzy S. Krasiński, Y. B. Band

Published Mar 1, 1993• 6 citations
Publisher

Abstract

A new method of efficient sum-frequency generation for broadband input fields is theoretically analyzed and experimentally demonstrated. The method involves using an arrangement with two or more nonlinear mixing crystals, with a time-delay line situated between the crystals, for one of the fundamental fields relative to the other. The delay line temporally shifts the fundamental fields, one relative to another, by a time longer than their coherence time. The improvement in efficiency for sum-frequency generation using this method is much higher than for difference-frequency generation.

DOI
10.1364/ol.18.000331

Related papers

Sum- and difference-frequency generation for broadband input fields

Y. B. Band, Czesław Radzewicz, Jerzy S. Krasiński

We analyze the dynamics of sum-frequency generation (SFG) and difference-frequency generation (DFG) for broadband input fields. We demonstrate that amplitude modulation of the input fields significantly affects conversion efficiency of SFG and DFG, but frequency modulation does not affect conversion efficiency. Analytic results for SFG and DFG output-field intensities are thereby available for arbitrary fields. Self- and cross-phase modulation can affect the dynamics in the limit of very high field strengths, but these effects are of higher nonlinearity and therefore usually negligible. The quantum efficiency of DFG is shown to be generally higher than SFG, but the energy efficiency is much lower if the difference frequency is significantly less than the input frequencies. Optimal SFG quantum conversion efficiency for such systems approaches that of second-harmonic generation only if the quantum fluence (total number of photons) in the two input beams are equal. Optimal DFG quantum conversion efficiency occurs when the number of photons of frequency ${\mathrm{\ensuremath{\omega}}}_{2}$ is small yet sufficient for significant stimulation. A recently developed method for obtaining efficient SFG for multimode input fields is theoretically analyzed. The method involves using an arrangement with two or more nonlinear mixing crystals with a time-delay line situated between the crystals that delays one of the fundamental fields relative to the other. The efficiency in the second crystal depends on the cross-correlation function of the two fundamental fields upon leaving the first nonlinear crystal. The time-delay method is not effective for multimode DFG.

Physical Review A•Jan 1, 1994•11 citations

Maximizing Sum Frequency Generation Efficiency

Yutian Zhang

In this thesis, high-efficiency frequency conversion Sum Frequency Generation (SFG) is theoretically analyzed and experimentally demonstrated. Our approach to SFG consists of two input phase conjugated broadband signal and idler beams undergoing SFG. By using the signal waveform as a gating beam, a specific mode may be recognized and separated out, providing a promising method for mode selection. The signal and idler are produced by a monochromatic pump and a broadband signal through Difference Frequency Generation (DFG). To obtain good mode selectivity, high conversion efficiency of the selected mode is required. We study the factors that influence the conversion efficiency of the selected mode, like the length of the waveguide and the power of the gating beam. The highest conversion efficiency of the mode achieved is over 90%. By breaking the correlation between mode and gating beams, we find around 40% conversion efficiency of the mismatched mode.

•Nov 1, 2022•0 citations

Efficient broadband sum and difference frequency generation with a single chirped quasi-phase-matching crystal

Andon A. Rangelov

We propose an efficient broadband frequency generation technique for two collinear optical parametric processes $ω_3=ω_1+ω_2$ and $ω_4=ω_1-ω_2$. It exploits chirped quasi-phase-matched gratings, which in the undepleted pump approximation regime perform population transfer that is analogous to adiabatic population transfer in a three-state ``vee'' quantum system. The energy of the input fields is transferred adiabatically either into $ω_3$ or $ω_4$ field, depending on which of the two phase matchings occurs first by the local modulation period in the crystal. One can switch the output between $ω_3$ and $ω_4$ by inverting the direction of the local modulation sweep, which corresponds to a rotation of the crystal by angle $π$

arXiv:1202.5580•Feb 24, 2012•0 citations

Optimal sum-frequency generation processes

Haifei Zhu, Yonggang Xu, Zhanrong Zhou +1 more

Sum-frequency generation in nonlinear optics is a key technology enabling optical frequency conversion. However, how to most effectively enhance the frequency conversion efficiency in nonlinear crystals remains a fundamental problem; shorter crystal length and lower pump intensity while maintaining high-efficiency frequency conversion are critical for enhancing device integration potential and improving device performance in practical sum-frequency generation (SFG) device design. This study employed the Pontryagin maximum principle to investigate the SFG process. A cost functional was formulated that complies with the minimum constraint during SFG, enabling the derivation of optimal control parameters. A central finding revealed an inverse proportionality between the coupling coefficient and the crystal length: for a given crystal length, the pump intensity in the SFG is minimized, and vice versa. The optimal evolution trajectory follows a geodesic path on the Bloch sphere surface, representing the minimal-length evolutionary path from the signal field to the sum-frequency field. This geodesic behavior also indicates that the loss and absorption of the optical field in the crystal medium vanish during SFG. Furthermore, the crystal modulation period for the SFG is determined using the optimal phase-matching function. These results offer valuable insights for the design of compact optical chips and nonlinear optical devices.

Journal of the Optical Society of America B•Feb 4, 2026•0 citations

Spectra of second harmonic generation and sum frequency generation for multimode fields

Jerzy S. Krasiński, Donald F. Heller, Jay R. Ackerhalt +1 more

The theory of three wave mixing was formulated in a classic paper by Armstrong, Bloembergen, Ducuing, and Pershan over 25 years ago.1 A theoretical description of three wave mixing for multimode time-dependent input fields (as opposed to cw single frequency time independent input fields) has recently been presented.2 Analytic solutions were developed for die time-dependent intensities of the output fields. These solutions differ dramatically from those for single-mode fields. New frequencies in the sum-frequency output spectrum and in the input-field output spectrum are created and grow in magnitude as the input intensities are increased. The output spectrum broadens under conditions of strong nonlinear coupling, ultimately reaching the phasematched bandwidth limit. Here, we review the results presented in Ref. 2 for sum frequency generation (SFG) and explicidy compare these results with those for second harmonic generation (SHG). We show that SHG cannot be described as a limit of the SFG formalism for multimode fields. The SFG formulation for the interaction of photons close to frequency ω1 with photons close to frequency ω2 producing photons close to frequency ω 3= ω 1+ ω 2 does not allow ω1(ω2) photons to interact with each other to produce photons close to frequency 2ω1(2ω2). This self interaction is crucial for SHG and must be incorporated. Therefore, a separate formulation is used to describe SHG with multimode input fields.

Nonlinear Dynamics in Optical Systems•Jan 1, 1990•0 citations

Efficient Broadband Frequency Conversion via Shortcuts to Adiabaticity

Koushik Paul, Qian Kong, Xi Chen

Abstract The method of adiabatic frequency conversion, in analogy with a two‐level atomic system, has been put forward recently and verified experimentally to achieve robust frequency mixing processes such as sum and difference frequency generation. Here a comparative study of efficient frequency mixing using various techniques of shortcuts to adiabaticity such as counter‐diabatic driving and invariant‐based inverse engineering is presented. It is shown here that it is possible to perform sum frequency generation by properly designing the poling structure of a periodically poled crystal and the coupling between the input lights and the crystal. The required crystal length for frequency conversion significantly decreases beyond the adiabatic limit. This approach significantly improves the robustness of the process against the variation in temperature as well as the signal frequency. By introducing a single parameter control technique with constant coupling and combining with the inverse engineering, perturbation theory, and optimal control, it is shown that the phase mismatch can be further optimized with respect to the fluctuations of input wavelength and crystal temperature that results into a novel experimentally realizable mixing scheme.

arXiv:2207.01349•Advanced Quantum Technologies•Oct 11, 2022•5 citations
A new method of efficient sum-frequency generation for broadband input fields is theoretically analyzed and experimentally demonstrated. The method involves using an arrangement with two or more nonlinear mixing crystals, with a time-delay line situated between the crystals, for one of the fundamental fields relative to the other. The delay line temporally shifts the fundamental fields, one relative to another, by a time longer than their coherence time. The improvement in efficiency for sum-frequency generation using this method is much higher than for difference-frequency generation.
We analyze the dynamics of sum-frequency generation (SFG) and difference-frequency generation (DFG) for broadband input fields. We demonstrate that amplitude modulation of the input fields significantly affects conversion efficiency of SFG and DFG, but frequency modulation does not affect conversion efficiency. Analytic results for SFG and DFG output-field intensities are thereby available for arbitrary fields. Self- and cross-phase modulation can affect the dynamics in the limit of very high field strengths, but these effects are of higher nonlinearity and therefore usually negligible. The quantum efficiency of DFG is shown to be generally higher than SFG, but the energy efficiency is much lower if the difference frequency is significantly less than the input frequencies. Optimal SFG quantum conversion efficiency for such systems approaches that of second-harmonic generation only if the quantum fluence (total number of photons) in the two input beams are equal. Optimal DFG quantum conversion efficiency occurs when the number of photons of frequency ${\mathrm{\ensuremath{\omega}}}_{2}$ is small yet sufficient for significant stimulation. A recently developed method for obtaining efficient SFG for multimode input fields is theoretically analyzed. The method involves using an arrangement with two or more nonlinear mixing crystals with a time-delay line situated between the crystals that delays one of the fundamental fields relative to the other. The efficiency in the second crystal depends on the cross-correlation function of the two fundamental fields upon leaving the first nonlinear crystal. The time-delay method is not effective for multimode DFG.
In this thesis, high-efficiency frequency conversion Sum Frequency Generation (SFG) is theoretically analyzed and experimentally demonstrated. Our approach to SFG consists of two input phase conjugated broadband signal and idler beams undergoing SFG. By using the signal waveform as a gating beam, a specific mode may be recognized and separated out, providing a promising method for mode selection. The signal and idler are produced by a monochromatic pump and a broadband signal through Difference Frequency Generation (DFG). To obtain good mode selectivity, high conversion efficiency of the selected mode is required. We study the factors that influence the conversion efficiency of the selected mode, like the length of the waveguide and the power of the gating beam. The highest conversion efficiency of the mode achieved is over 90%. By breaking the correlation between mode and gating beams, we find around 40% conversion efficiency of the mismatched mode.
We propose an efficient broadband frequency generation technique for two collinear optical parametric processes ω3=ω1+ω2ω_3=ω_1+ω_2ω3​=ω1​+ω2​ and ω4=ω1−ω2ω_4=ω_1-ω_2ω4​=ω1​−ω2​. It exploits chirped quasi-phase-matched gratings, which in the undepleted pump approximation regime perform population transfer that is analogous to adiabatic population transfer in a three-state ``vee'' quantum system. The energy of the input fields is transferred adiabatically either into ω3ω_3ω3​ or ω4ω_4ω4​ field, depending on which of the two phase matchings occurs first by the local modulation period in the crystal. One can switch the output between ω3ω_3ω3​ and ω4ω_4ω4​ by inverting the direction of the local modulation sweep, which corresponds to a rotation of the crystal by angle πππ
Sum-frequency generation in nonlinear optics is a key technology enabling optical frequency conversion. However, how to most effectively enhance the frequency conversion efficiency in nonlinear crystals remains a fundamental problem; shorter crystal length and lower pump intensity while maintaining high-efficiency frequency conversion are critical for enhancing device integration potential and improving device performance in practical sum-frequency generation (SFG) device design. This study employed the Pontryagin maximum principle to investigate the SFG process. A cost functional was formulated that complies with the minimum constraint during SFG, enabling the derivation of optimal control parameters. A central finding revealed an inverse proportionality between the coupling coefficient and the crystal length: for a given crystal length, the pump intensity in the SFG is minimized, and vice versa. The optimal evolution trajectory follows a geodesic path on the Bloch sphere surface, representing the minimal-length evolutionary path from the signal field to the sum-frequency field. This geodesic behavior also indicates that the loss and absorption of the optical field in the crystal medium vanish during SFG. Furthermore, the crystal modulation period for the SFG is determined using the optimal phase-matching function. These results offer valuable insights for the design of compact optical chips and nonlinear optical devices.
The theory of three wave mixing was formulated in a classic paper by Armstrong, Bloembergen, Ducuing, and Pershan over 25 years ago.1 A theoretical description of three wave mixing for multimode time-dependent input fields (as opposed to cw single frequency time independent input fields) has recently been presented.2 Analytic solutions were developed for die time-dependent intensities of the output fields. These solutions differ dramatically from those for single-mode fields. New frequencies in the sum-frequency output spectrum and in the input-field output spectrum are created and grow in magnitude as the input intensities are increased. The output spectrum broadens under conditions of strong nonlinear coupling, ultimately reaching the phasematched bandwidth limit. Here, we review the results presented in Ref. 2 for sum frequency generation (SFG) and explicidy compare these results with those for second harmonic generation (SHG). We show that SHG cannot be described as a limit of the SFG formalism for multimode fields. The SFG formulation for the interaction of photons close to frequency ω1 with photons close to frequency ω2 producing photons close to frequency ω 3= ω 1+ ω 2 does not allow ω1(ω2) photons to interact with each other to produce photons close to frequency 2ω1(2ω2). This self interaction is crucial for SHG and must be incorporated. Therefore, a separate formulation is used to describe SHG with multimode input fields.
Abstract The method of adiabatic frequency conversion, in analogy with a two‐level atomic system, has been put forward recently and verified experimentally to achieve robust frequency mixing processes such as sum and difference frequency generation. Here a comparative study of efficient frequency mixing using various techniques of shortcuts to adiabaticity such as counter‐diabatic driving and invariant‐based inverse engineering is presented. It is shown here that it is possible to perform sum frequency generation by properly designing the poling structure of a periodically poled crystal and the coupling between the input lights and the crystal. The required crystal length for frequency conversion significantly decreases beyond the adiabatic limit. This approach significantly improves the robustness of the process against the variation in temperature as well as the signal frequency. By introducing a single parameter control technique with constant coupling and combining with the inverse engineering, perturbation theory, and optimal control, it is shown that the phase mismatch can be further optimized with respect to the fluctuations of input wavelength and crystal temperature that results into a novel experimentally realizable mixing scheme.