42s-atomic

A small library of routines for calculating interesting quantities useful in Atomic Physics and Ultrafast Optics.

Build instructions

The HP42s raw files are generated by typing

rake

in a command line near you. Requires Ruby and Perl to work. The raw files are created in the subfolder build/raw/. For convenience, they are all concatenated together into a bundled raw file called build/42s-atomic.raw, which, when loaded, imports all the routines in one fell swoop.

To translate from text format to raw files, the txt2raw.pl by Vini Matangrano is used.

Routines

LELEV

Load first ionization energies (in eV) into a matrix named ELEV. (Data source: NIST)

LCONST

Load constants useful for atomic units, etc. See constants.yaml for which constants are defined.

OMEGAU

Given a wavelength λ in SI units, calculate the angular frequency ω = 2πc₀/λ, storing the result in atomic units in the variable OMEGAU and in electronvolts in OMEGAEV.

ATOMIP

Given an atomic number Z, store the ionization potential Iₚ (in atomic units) in the variable ATOMIP.

UP

Calculate the ponderomotive potential Uₚ = I/4ω² from the field intensity I and the angular frequency ω (all in atomic units; uses the subroutine OMEGAU).

HHGCUT

Calculate the classical cut-off in HHG, Wₖ₋ₘₐₓ = 3.17Uₚ + Iₚ given an intensity, a wavelength and an atomic number, and store the result as

CUTOFF

atomic units,

CUTOEV

electronvolts,

CUTOFQ

harmonic orders (i.e. Wₖ₋ₘₐₓ/ω).

(uses the subroutines ATOMIP and UP).

HHGEXC

Calculate the typical excursion of an electron in HHG, given by <x> = E/ω², where the electric field amplitude E = √I. The result is stored in the variables EXCAU and EXCSI in Bohr radii and metres, respectively (uses the subroutine UP).

KELDYSH

Calculate the Keldysh parameter γ = √(Iₚ/2Uₚ) and stores the result in the variable GAMMA (uses the subroutines ATOMIP and UP).

Caveats

These routines are only tested using Free42, as I don’t own a real HP42s device.