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

Conference on Lasers and Electro-Optics

Confined Excitons with Ultrafast Radiative Decay Time Less than 100 fs Enabling Survival at Room Temperature

Masayoshi Ichimiya, Keita Mochizuki, Masaaki Ashida, Hideki Yasuda, Hajime Ishihara, Tadashi Itoh

Published Jan 1, 2010• 0 citations
Publisher

Abstract

Temperature dependence of degenerate four-wave mixing signal in high-quality CuCl thin films was investigated. We observed the signal of modes with large radiative width at high temperatures due to ultrafast radiative decay faster than dephasing.
DOI
10.1364/qels.2010.qwg1

Related papers

Ultrafast radiative decay of confined excitons due to long-range coherent coupling with radiation wave

Masayoshi Ichimiya, Masaaki Ashida, Hideki Yasuda +2 more

Transient grating spectrum and the delay time dependence are investigated in a CuCl thin film. The structures for complex eigenmodes and the ultrafast radiative decay rates of excitons below 200 fs are observed.

Quantum Electronics and Laser Science Conference•May 1, 2007•1 citation

Thermal free ultrafast luminescence due to nonlocal light-matter interaction (Conference Presentation)

Masayoshi Ichimiya, Takuya Matsuda, Hajime Ishihara +1 more

We demonstrate ultrafast superradiance showing 10-fs decay due to the nonlocal interaction between light waves and exciton waves in CuCl mesoscopic thin films. This time constant is comparable with the thermal dephasing even at room temperature. Actually, we observed photoluminescence signal from one confined mode of translational motion of the exciton surviving at room temperature. In addition, temperature dependence of the photoluminescence spectra with multiple peaks was reproduced well by theoretical calculation. This finding opens a new avenue of “thermal free photonics”, where the exciton coherence is utilized at higher temperature.

Ultrafast Phenomena and Nanophotonics•Mar 10, 2020•0 citations

Resonant Optical Kerr Response with Ultrashort Decay Time by Nonlocal Wave Coupling of Light and Excitons

Masayoshi Ichimiya, Takayuki Umakoshi, H. Murata +3 more

Resonant optical Kerr effects have been investigated in high-quality CuCl thin films. The peculiar spectral feature and ultrafast response below 200 fs due to a long-range coherent coupling between light and multinode-type excitons are observed.

International Conference on Ultrafast Phenomena•Jan 1, 2014•0 citations

Observation of Superradiance by Nonlocal Wave Coupling of Light and Excitons in CuCl Thin Films

Masayoshi Ichimiya, Masaaki Ashida, Hideki Yasuda +2 more

We report the observation of a remarkably strong coupling between light and a multinode-type exciton. The observed radiative decay time reaches the order of 100 fs, which is much faster than the dephasing process of nonradiative scattering. In this high-speed superradiance, the light wave and the excitonic wave in a high-quality thin film form a harmonized wave-wave coupling over a range of multiple wavelengths. This mechanism contradicts the conventional physical description of light-matter interaction based on the long-wavelength approximation.

Physical Review Letters•Dec 14, 2009•45 citations

Room Temperature Degenerate Four-Wave Mixing Due to Ultrafast Radiative Decay of Confined Excitons

Masayoshi Ichimiya, Masaaki Ashida, Hideki Yasuda +2 more

Get PDF Email Share Share with Facebook Tweet This Post on reddit Share with LinkedIn Add to CiteULike Add to Mendeley Add to BibSonomy Get Citation Copy Citation Text M. Ichimiya, M. Ashida, H. Yasuda, H. Ishihara, and T. Itoh, "Room Temperature Degenerate Four-Wave Mixing Due to Ultrafast Radiative Decay of Confined Excitons," in Conference on Lasers and Electro-Optics/International Quantum Electronics Conference, OSA Technical Digest (CD) (Optical Society of America, 2009), paper IWA1. Export Citation BibTex Endnote (RIS) HTML Plain Text Citation alert Save article

Conference on Lasers and Electro-Optics•Jan 1, 2009•0 citations

Ultrafast All-Optical Control of Excitons Confined in GaAs Thin Films

Osamu Kojima, Ayumi Miyagawa, Takashi Kita +2 more

We demonstrate the possibility of ultrafast optical control of excitons confined in GaAs thin films. The intensity of a two-beam degenerate four-wave-mixing signal changes with an increase in the power of each pulse. The signal intensity monotonically decreases after reaching the maximum. Peaks appear at different excitation powers for k 1 and k 2 pulses, which suggests that the decrease in the signal intensity is caused by excitonic Rabi oscillations. Our results demonstrate the possibility of ultrafast control of the exciton population by using optical pulses.

Applied Physics Express•Nov 14, 2008•6 citations
We demonstrate ultrafast superradiance showing 10-fs decay due to the nonlocal interaction between light waves and exciton waves in CuCl mesoscopic thin films. This time constant is comparable with the thermal dephasing even at room temperature. Actually, we observed photoluminescence signal from one confined mode of translational motion of the exciton surviving at room temperature. In addition, temperature dependence of the photoluminescence spectra with multiple peaks was reproduced well by theoretical calculation. This finding opens a new avenue of “thermal free photonics”, where the exciton coherence is utilized at higher temperature.
We report the observation of a remarkably strong coupling between light and a multinode-type exciton. The observed radiative decay time reaches the order of 100 fs, which is much faster than the dephasing process of nonradiative scattering. In this high-speed superradiance, the light wave and the excitonic wave in a high-quality thin film form a harmonized wave-wave coupling over a range of multiple wavelengths. This mechanism contradicts the conventional physical description of light-matter interaction based on the long-wavelength approximation.
Get PDF Email Share Share with Facebook Tweet This Post on reddit Share with LinkedIn Add to CiteULike Add to Mendeley Add to BibSonomy Get Citation Copy Citation Text M. Ichimiya, M. Ashida, H. Yasuda, H. Ishihara, and T. Itoh, "Room Temperature Degenerate Four-Wave Mixing Due to Ultrafast Radiative Decay of Confined Excitons," in Conference on Lasers and Electro-Optics/International Quantum Electronics Conference, OSA Technical Digest (CD) (Optical Society of America, 2009), paper IWA1. Export Citation BibTex Endnote (RIS) HTML Plain Text Citation alert Save article
We demonstrate the possibility of ultrafast optical control of excitons confined in GaAs thin films. The intensity of a two-beam degenerate four-wave-mixing signal changes with an increase in the power of each pulse. The signal intensity monotonically decreases after reaching the maximum. Peaks appear at different excitation powers for k 1 and k 2 pulses, which suggests that the decrease in the signal intensity is caused by excitonic Rabi oscillations. Our results demonstrate the possibility of ultrafast control of the exciton population by using optical pulses.