[salmon-user:00389] Problems about Pump probe calculation of Strong field light interaction with crystal using SALMON

[u301...@connect.hku.hk]

Dear Salmon developers and users,

Greetings to all.

I am now trying to use Salmon to do pump-probe calculations, I should use strong field light to 1V/A (10^10-10^13W/cm^2) to get high harmonic generation. I have few questions:

1. How can I separate the signal from pump and probe, respectively. Because the interaction between this two beams are not linear, so we cannot just easily do subtraction if I understand correctly.
2. If I use circular polarized input beam, how can I define the output beam polarization ?
3. Or if we have some other solutions to do strong field pump-probe calculations, for example, using non collinear calculation setup?

Looking for your reply!

Thank you very much ~

Best regards,

Tangmeng

[Otobe Tomohito]

Dear Tangmeng,

Thank you for your questions.

1. Separating Pump and Probe Signals

The usual approach is to perform two separate calculations:

    • One with both pump and probe pulses.

    • Another with the pump pulse only.

Then, subtract the pump-only response from the combined result to isolate the probe contribution.

2. Determining Output Polarization

You can check the polarization of the emitted light by analyzing the vector potential or the current components (x, y, z) in the output. These will indicate the polarization state.

3. Alternative Methods

I’m not entirely sure what kind of alternatives you had in mind, but for strong-field interactions, real-time calculations are generally the only viable approach.

I hope this helps clarify your questions. Please feel free to reach out if you need further details or examples.

Best regards,

Tomohito Otobe

乙部 智仁

 

Tomohito Otobe

 

Senior Principal Researcher

Kansai Photon Science Institute (KPSI)

National Institutes for Quantum Science and Technology (QST)

 

otobe.t...@qst.go.jp

+81-774-80-8899

 

 

差出人: u301...@connect.hku.hk <u301...@connect.hku.hk>
日付: 火曜日, 2026年1月13日 12:14
宛先: salmon-user <salmo...@salmon-tddft.jp>
件名: [salmon-user:00389] Problems about Pump probe calculation of Strong field light interaction with crystal using SALMON

[u301...@connect.hku.hk]

Dear Prof. Tomohito Otobe,

Thank you very much for your reply!

Best Regards,

Tangmeng

---

发件人: Otobe Tomohito <otobe.t...@qst.go.jp>
发送时间: 2026年1月16日 10:49
收件人: salmo...@salmon-tddft.jp <salmo...@salmon-tddft.jp>
主题: [salmon-user:00390] Re: Problems about Pump probe calculation of Strong field light interaction with crystal using SALMON

 

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