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

Enhanced nonlinearity and transparency via autoionizing resonance

Takashi Nakajima

Published Jun 1, 2000• 30 citations
Publisher

Abstract

The nonlinear response of an autoionizing medium in which coherence is established essentially by nonradiative interactions is analyzed. It is found that, by proper tuning of two radiation fields, the third-order nonlinearities can be enhanced while the absorption is canceled. The proposed scheme is particularly useful for enhancing nonlinearities in the VUV region.

DOI
10.1364/ol.25.000847

Related papers

Tunable Resonant Enhancement in Nonlinear Optical Frequency Mixing

Arlee V. Smith

The ability to introduce additional resonances in the nonlinear optical susceptibility of a medium by the injection of an additional radiation field is an attractive possibility from the standpoint of efficient tunable frequency mixing processes in the VUV. The possibility of such processes suggest themselves in previous observations in atomic mercury where an enhancement of several orders of magnitude in the third harmonic generation efficiency has been reported when the input frequency is four-photon resonant with the 6S → 6D transition(1).

Topical Meeting on Laser Techniques in the Extreme Ultraviolet•Jan 1, 1984•0 citations

Efficient sum-frequency mixing through transparency induced by autoionization

Takashi Nakajima

It is shown that efficient sum-frequency mixing is possible through transparency induced by autoionization. Tuning the incident laser frequencies to the absorption minimum of an autoionizing resonance for the generated wave greatly reduces the linear absorption of the generated wave while third-order susceptibility is still enhanced. The proposed scheme does not require any strong radiative couplings and would be particularly useful for the generation of short-wavelength radiation.

Optics Letters•Jan 15, 2002•2 citations

Enhancement of the nonlinearity via interacting dark resonances

Xiang-an Yan, Liqiang Wang

A scheme for large enhancement of the third-order nonlinearity in a four-level system with double dark resonances is proposed. We obtain an analytical expression for the linear susceptibility and nonlinear susceptibility of a weak probe field and show that the properties of double electromagnetically induced transparency and the Kerr nonlinearity can be modified significantly by changing the ratio of the two coupling fields. A physical understanding of our numerical results using the dressed-state approach is presented. The obtained large nonlinearity with vanishing absorption can be used to generate optical solitons, polarization phase gates and optical Kerr shutters.

Cross Strait Radio Science and Wireless Technology Conference (CSRSWTC)•Jul 1, 2011•0 citations

Role of atomic coherence effects in four-wave mixing using autoionizing resonances

M. Anscombe, Rebeca de Nalda, İbrahim Küçükkara +1 more

The generation of tunable, nanosecond-pulsed extreme-ultraviolet (EUV) light $(84.92\mathrm{nm}$ to $84.97\mathrm{nm}$ $\ensuremath{\sim}14.6\mathrm{eV})$ using four-wave mixing in optically deep krypton gas was investigated experimentally and theoretically. The sum-frequency mixing scheme generated light from two overlapping autoionizing resonances, ${17s}^{\ensuremath{'}}$ and ${15d}^{\ensuremath{'}}$. We investigated whether the laser-induced atomic coherence effect of electromagnetically induced transparency (EIT) could enhance the intensity of the EUV light generated. The maximum EUV output was seen from the region where the ${15d}^{\ensuremath{'}}$ autoionizing resonance has a transparency window due to Fano-type quantum interference. An analytical model using appropriate atomic parameters explains how background absorption can prevent EIT enhancement of EUV generation; and shows how a background Raman-like coupling term in the nonlinear susceptibility can well describe the measured EUV generation spectrum.

Physical Review A•Oct 8, 2003•2 citations

Pump-induced transparency and enhanced third-harmonic generation near an autoionizing state

S. J. van Enk, Jian Zhang, P. Lambropoulos

We analyze an electromagnetically induced transparency near an autoionizing state, which is at the same time stabilized against ionization. We show that the effect is fairly general as long as only one continuum is involved. We compare the efficiency for third-harmonic generation in this system with that in an intermediate two-photon resonance system, and discuss the advantages of the former. Explicit calculations are presented for a specific autoionizing resonance in Ca.

Physical Review A•Oct 1, 1994•13 citations

Enhancing Kerr Nonlinearity Via Interacting Dark Resonances

Jianping Song

A theoretical investigation was carried out into the program for enhancing the Kerr nonlinearity by interacting double dark states resonances.Using density-matrix equations and perturbative iterative method,the dependence of the real part of the third-order susceptibility on the variation of the additional coherent driving field detuning was derived.It is found that the maximal Kerr nonlinearity induced by interacting dark resonances increases with increment of the detuning and enters gradually the electromagnetically induced transparency window,in which the corresponding linear absorption vanishes,moreover,by utilizing the dressed state theory,physical mechanisms for the results were presented.The realization of the giant Kerr nonlinearity with vanishing absorption is possible in a generic four-level system with double dark resonances.

ACTA PHOTONICA SINICA•Jan 1, 2009•0 citations
The nonlinear response of an autoionizing medium in which coherence is established essentially by nonradiative interactions is analyzed. It is found that, by proper tuning of two radiation fields, the third-order nonlinearities can be enhanced while the absorption is canceled. The proposed scheme is particularly useful for enhancing nonlinearities in the VUV region.
The ability to introduce additional resonances in the nonlinear optical susceptibility of a medium by the injection of an additional radiation field is an attractive possibility from the standpoint of efficient tunable frequency mixing processes in the VUV. The possibility of such processes suggest themselves in previous observations in atomic mercury where an enhancement of several orders of magnitude in the third harmonic generation efficiency has been reported when the input frequency is four-photon resonant with the 6S → 6D transition(1).
A scheme for large enhancement of the third-order nonlinearity in a four-level system with double dark resonances is proposed. We obtain an analytical expression for the linear susceptibility and nonlinear susceptibility of a weak probe field and show that the properties of double electromagnetically induced transparency and the Kerr nonlinearity can be modified significantly by changing the ratio of the two coupling fields. A physical understanding of our numerical results using the dressed-state approach is presented. The obtained large nonlinearity with vanishing absorption can be used to generate optical solitons, polarization phase gates and optical Kerr shutters.
The generation of tunable, nanosecond-pulsed extreme-ultraviolet (EUV) light (84.92nm(84.92\mathrm{nm}(84.92nm to 84.97nm84.97\mathrm{nm}84.97nm $\ensuremath{\sim}14.6\mathrm{eV})$ using four-wave mixing in optically deep krypton gas was investigated experimentally and theoretically. The sum-frequency mixing scheme generated light from two overlapping autoionizing resonances, ${17s}^{\ensuremath{'}}$ and ${15d}^{\ensuremath{'}}$. We investigated whether the laser-induced atomic coherence effect of electromagnetically induced transparency (EIT) could enhance the intensity of the EUV light generated. The maximum EUV output was seen from the region where the ${15d}^{\ensuremath{'}}$ autoionizing resonance has a transparency window due to Fano-type quantum interference. An analytical model using appropriate atomic parameters explains how background absorption can prevent EIT enhancement of EUV generation; and shows how a background Raman-like coupling term in the nonlinear susceptibility can well describe the measured EUV generation spectrum.
A theoretical investigation was carried out into the program for enhancing the Kerr nonlinearity by interacting double dark states resonances.Using density-matrix equations and perturbative iterative method,the dependence of the real part of the third-order susceptibility on the variation of the additional coherent driving field detuning was derived.It is found that the maximal Kerr nonlinearity induced by interacting dark resonances increases with increment of the detuning and enters gradually the electromagnetically induced transparency window,in which the corresponding linear absorption vanishes,moreover,by utilizing the dressed state theory,physical mechanisms for the results were presented.The realization of the giant Kerr nonlinearity with vanishing absorption is possible in a generic four-level system with double dark resonances.