Operation of the sapphire Cerenkov laser

Fisch, Emily; Walsh, J. E.

doi:10.1063/1.107322

Cited by 18 publications

(15 citation statements)

References 2 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The reason seems to be the low electron current density. The stimulated emission at 100 GHz has already been reported for a similar configuration to that used by us, 19,20 but the electron density in that experiment was almost 100 times larger than that in our experiment. We expect that the effect of the stimulated emission can be clarified by increasing the electron-beam current density by more than two orders of magnitude.…”

Section: Comparison Between Experiments and Theorymentioning

confidence: 35%

“…3,4 The Cherenkov laser has the possibility of operation at a relatively low voltage with a compact size. [12][13][14][15][16][17][18][19][20][21] Radiation of an electromagnetic wave at approximately 100 GHz from a Cherenkov laser with an electron acceleration voltage of 35-75 kV has been reported. 19 However, radiation in the optical frequency range obtained from a Cherenkov laser has not yet been observed.…”

Section: Introductionmentioning

confidence: 99%

“…[5][6][7][8][9][10][11][12][13][14][15][16][17][18][19][20] These devices utilize the kinetic energy of an electron beam in a vacuum, and the condition required to obtain the radiation and to amplify the electromagnetic wave is that the velocities of the electron beam and the electromagnetic wave coincide. Therefore, these devices can operate, in principle, over a very wide frequency range extending from the microwave to the x-ray regions of the electromagnetic spectrum.…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Optical emission from a high-refractive-index waveguide excited by a traveling electron beam

Kuwamura

Yamada

Okamoto

et al. 2008

Journal of Applied Physics

View full text Add to dashboard Cite

An optical emission scheme was demonstrated, in which a high-refractive-index waveguide is excited by a traveling electron beam in a vacuum environment. The waveguide was made of Si-SiO 2 layers. The velocity of light propagating in the waveguide was slowed down to 1/3 of that in free space due to the high refractive index of Si. The light penetrated partly into the vacuum in the form of a surface wave. The electron beam was emitted from an electron gun and propagated along the surface of the waveguide. When the velocity of the electron coincided with that of the light, optical emission was observed. This emission is a type of Cherenkov radiation and is not conventional cathode luminescence from the waveguide materials because Si and SiO 2 are transparent to light at the emitted wavelength. This type of emission was observed in an optical wavelength range from 1.2 to 1.6 m with an electron acceleration voltage of 32-42 kV. The characteristics of the emitted light, such as the polarization direction and the relation between the acceleration voltage of the electron beam and the optical wavelength, coincided well with the theoretical results. The coherent length of an electron wave in the vacuum was confirmed to be equal to the electron spacing, as found by measuring the spectral profile of the emitted light.

show abstract

Section: Comparison Between Experiments and Theorymentioning

confidence: 35%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Optical emission from a high-refractive-index waveguide excited by a traveling electron beam

Kuwamura

Yamada

Okamoto

et al. 2008

Journal of Applied Physics

View full text Add to dashboard Cite

show abstract

“…The proposed configuration, which we call the double-slab type, in contrast to the extensively investigated resonator consisting of one dielectric plate (single-slab type) [7][8][9], confines the electromagnetic waves within a narrow region, which enhances the interaction between electrons and the electromagnetic waves. The proposed configuration, which we call the double-slab type, in contrast to the extensively investigated resonator consisting of one dielectric plate (single-slab type) [7][8][9], confines the electromagnetic waves within a narrow region, which enhances the interaction between electrons and the electromagnetic waves.…”

Section: Introductionmentioning

confidence: 99%

“…Compared to the CFELs studied in other research institutions, our design has the distinctive characteristic that the optical resonator consists of two dielectric plates. The proposed configuration, which we call the double-slab type, in contrast to the extensively investigated resonator consisting of one dielectric plate (single-slab type) [7][8][9], confines the electromagnetic waves within a narrow region, which enhances the interaction between electrons and the electromagnetic waves. Thus the gain (the amplification factor of the electromagnetic waves) can be increased.…”

Section: Introductionmentioning

confidence: 99%

Analysis of the Double‐Slab Type Cherenkov Free‐Electron Laser Resonator

Yoshida

Munemoto

Kimura

et al. 2014

Elect Comm in Japan

View full text Add to dashboard Cite

A compact Cherenkov free-electron laser operating in the terahertz spectral range is being developed. Analysis of the double-slab type optical resonator has clarified the resonant frequency, the small signal gain, and the saturation power of the device. One-dimensional simulation code predicted a small signal gain of 6% with a 50 kV/3.6 mA electron beam. The saturation power was estimated to be 90 mW. The out-coupling structure of the resonator was designed using 3D simulation code. A transmittivity of 3.0% and a spread angle of 0.4 rad were predicted. C⃝ 2014 Wiley Periodicals, Inc. Electron Comm Jpn, 97(6): 16-23, 2014; Published online in Wiley Online Library (wileyonlinelibrary.com).

show abstract

High‐Q Metallic Fano Metamaterial for Highly Efficient Cerenkov Lasing

Kim

Baek

Bhattacharya

et al. 2018

Advanced Optical Materials

View full text Add to dashboard Cite

development of such CR-based applications is limited by thermal and dielectric breakdown issues. [3,4] Another limitation is that, due to the velocity threshold, large facilities are required to generate highly energetic particles. These limitations restrict the upper and lower size and performance boundaries in vital applications. Nowadays, metallic metamaterial devices have been proposed, which overcome the limitations of conventional Cerenkov devices to realize reversed CR from the negative-refractive index, [5] the ultralow threshold of kinetic energy in hyperbolic metamaterials, [6] and various metallic metamaterials comprised of subwavelength slits. [7][8][9] However, the realization of a high quality factor (Q) is still an outstanding roadblock for practical Cerenkov devices. Previous works on Cerenkov lasing (CL) using mirrors were limited by a lower electron beam impedance due to the interaction device and the radio-frequency (RF) coupling mechanism. [4,10] Here, to achieve a high Q for highly efficient CL, we focus on maximally trapping the electromagnetic Cerenkov radiation wave to extend its interaction with the electron beam and on controlling the radiation damping, as has been described in Rayleigh scattering to maximize the efficiency of CL. In this paper, we demonstrate that the interplay between an extremely low group velocity from the infinite transverse permittivity of the anisotropic metamaterials and the subradiant A high-quality-factor (high-Q) metallic Fano metamaterial is demonstrated both experimentally and theoretically. This material is suitable for highly efficient Cerenkov lasing in which subwavelength metallic slits are arranged to form asymmetric unit cells. In contrast to conventional dielectric Cerenkov or Smith-Purcell devices, in the proposed device, convection electrons traverse the high-Q metallic metamaterial. The interplay between an extremely low group velocity from the infinite transverse permittivity of the anisotropic metamaterial and the subradiant damping from a Fano-type slit mode is shown to be responsible for the high-Q value, which is measured to be unprecedented at 700. The resulting improvement in the Cerenkov lasing efficiency is estimated to be more than two orders of magnitude using a particle-in-cell simulation.

show abstract

Operation of the sapphire Cerenkov laser

Cited by 18 publications

References 2 publications

Optical emission from a high-refractive-index waveguide excited by a traveling electron beam

Optical emission from a high-refractive-index waveguide excited by a traveling electron beam

Analysis of the Double‐Slab Type Cherenkov Free‐Electron Laser Resonator

High‐Q Metallic Fano Metamaterial for Highly Efficient Cerenkov Lasing

Contact Info

Product

Resources

About