# Photo-Ionization of Noble Gases: A Demonstration of Hybrid Coupled Channels Approach

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## Abstract

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## 1. Introduction

## 2. Hybrid Coupled Channels Method

## 3. Results

#### 3.1. One- and Two-Photon Cross-Sections of Neon

**Figure 1.**One-photon ionization cross-sections of Neon as a function of photon energy from haCC and from experiments [22]. haCC(4): Ionic basis consists of both $1{s}^{2}2{s}^{2}2{p}^{5}$ states and $1{s}^{2}2s2{p}^{6}$ state.

**Figure 2.**Two photon ionization cross-sections of Neon as a function of photon energy. The RMF and the TDRM results are from [12]. haCC(3): Ionic basis consists of only $1{s}^{2}2{s}^{2}2{p}^{5}$ states. haCC(4): Ionic basis consists of both $1{s}^{2}2{s}^{2}2{p}^{5}$ states and $1{s}^{2}2s2{p}^{6}$ state. The results from haCC(3) and haCC(4) are superposed.

#### 3.2. Five-Photon Ionization Rates from Argon

**Figure 3.**Five-photon ionization rates as a function of wavelength. The peak intensity of the laser fields used is ${10}^{13}W/c{m}^{2}$. The RMF results are from [14].

#### 3.3. Photo-Electron Spectra from Argon with 12 nm Wavelength Laser Fields

**Figure 4.**Total photo-electron spectra from Argon with linearly and circulary polarized 15 cycle, 12 nm wavelength, ${cos}^{2}$ envelope laser pulses with a peak intensity of $9\times {10}^{13}W/c{m}^{2}$. The figure shows the one- and two-photon ionization peaks.

**Figure 5.**Resolving photo-electron spectra from Argon with linearly polarized 12 nm wavelength laser fields. Left figure: dominant partial waves in the ionic channels 1:$\phantom{\rule{0.277778em}{0ex}}\left[Ne\right]3{s}^{2}3{p}_{x}^{2}3{p}_{y}3{p}_{z}^{2}$, 2:$\phantom{\rule{0.277778em}{0ex}}\left[Ne\right]3{s}^{2}3{p}_{x}^{2}3{p}_{y}^{2}3{p}_{z}$, 3:$\phantom{\rule{0.277778em}{0ex}}\left[Ne\right]3s3{p}^{6}$. The channel 2 is dominated by the s-d superposition. Right figure: Angle resolved spectra corresponding to the one-photon ionization double peak in Figure 4. The angle is defined with respect to the laser polarization direction.

## 4. Conclusions

## Acknowledgments

## Author Contributions

## Conflicts of Interest

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**MDPI and ACS Style**

Majety, V.P.; Scrinzi, A.
Photo-Ionization of Noble Gases: A Demonstration of Hybrid Coupled Channels Approach. *Photonics* **2015**, *2*, 93-103.
https://doi.org/10.3390/photonics2010093

**AMA Style**

Majety VP, Scrinzi A.
Photo-Ionization of Noble Gases: A Demonstration of Hybrid Coupled Channels Approach. *Photonics*. 2015; 2(1):93-103.
https://doi.org/10.3390/photonics2010093

**Chicago/Turabian Style**

Majety, Vinay Pramod, and Armin Scrinzi.
2015. "Photo-Ionization of Noble Gases: A Demonstration of Hybrid Coupled Channels Approach" *Photonics* 2, no. 1: 93-103.
https://doi.org/10.3390/photonics2010093