# Chirped Laser Pulse Effect on a Quantum Linear Oscillator

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## Abstract

**:**

## 1. Introduction

## 2. Results

_{0}are the charge, mass, and own frequency of oscillator. E(ω) is the Fourier transform of electric field strength in the laser pulse. Furthermore, we considered pulse with Gaussian envelope and the linear frequency chirp.

_{0}is the field amplitude, ω and τ are the carrier frequency and duration of laser pulse, α is the dimensionless chirp, and Δω is the spectral width of the pulse which is equal to

_{10}is the matrix element of the electric dipole moment for the 0 → 1 transition in the linear quantum oscillator. It is convenient for the analytical description of oscillator excitation to express the average number of absorbed quanta $\overline{n}$ via dimensionless parameters in the form

_{0}corresponding to the vibration of the CO molecule in harmonic approximation.

_{10}), this maximum became a minimum. When the inverse to (9) inequality held, two maxima appeared at the following detunings of the carrier frequency from the own oscillator frequency (according to Figure 1b):

## 3. Conclusions

## Author Contributions

## Funding

## Acknowledgments

## Conflicts of Interest

## References

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**Figure 1.**Spectrum of the excitation probability of transition 0 → 1 in quantum oscillator for weak field —E

_{0}= 10

^{−3}a.u. (

**a**) strong field—E

_{0}= 0.04 a.u. (

**b**) and different values of the dimensionless frequency chirp: solid line α = 0, dotted line—α = 0.5, dashed line—α = 1.

**Figure 2.**Excitation probability of transition 0 → 1 in the quantum oscillator as function of dimensionless pulse duration (β) for a weak field—E

_{0}= 10

^{−3}a.u. (

**a**) strong field—E

_{0}= 0.04 a.u. (

**b**) and different values of dimensionless chirp: solid line—α = 0, dotted line—α = 0.5, dashed line—α = 1.

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**MDPI and ACS Style**

Astapenko, V.A.; Sakhno, E.V.
Chirped Laser Pulse Effect on a Quantum Linear Oscillator. *Symmetry* **2020**, *12*, 1293.
https://doi.org/10.3390/sym12081293

**AMA Style**

Astapenko VA, Sakhno EV.
Chirped Laser Pulse Effect on a Quantum Linear Oscillator. *Symmetry*. 2020; 12(8):1293.
https://doi.org/10.3390/sym12081293

**Chicago/Turabian Style**

Astapenko, Valeriy A., and Evgeniya V. Sakhno.
2020. "Chirped Laser Pulse Effect on a Quantum Linear Oscillator" *Symmetry* 12, no. 8: 1293.
https://doi.org/10.3390/sym12081293