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Outline of the talk

Coherent radiation

Coherent radiation in XUV range

Theory of High-order Harmonic Generation (HHG

Future plan

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Coherent Radiation

In a wae if there i! a con!tant pha!e relation!hip "etween tw!eparated in !pace#time the wae i! !aid to hae !patial#temp

coherence$ %a!er! are the good !ource! of coherent radiation in i!i"le#I&

and al!o hae the other feature! li'e monochromaticity direc

Generation of coherent radiation at !horter waelength! i! anre!earch due to their application! in ariou! eld!$

Advantages of Coherent Radiation at shorwavelength*ul!e! of !hort pul!e duration (!u" femto!econd)

High !patial re!olution$

*ro"e for pla!ma of higher den!ity$

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Coherent radiation in !U" range

+on-linear cry!tal! are u!ed to produce coherent radiatio!horter waelength "y the generation of harmonic! of int

la!er pul!e!$

+on-linear cry!tal ha! limitation! on the minimum waele(,.. nm) due to the !trong a"!orption of radiation in!idcry!tal$

"nder#dense $lasma i! u!ed to produce higher order harm

it! interaction with inten!e ultra-!hort la!er pul!e!$The!e generated harmonic! are of the order of /..thof m

la!er fre0uency !o waelength! come! in the !oft 1-ray

The phenomena i! 'nown a! Higher order Harmonic Gen(HHG)$

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#heory of High-order Harmonic Generatio

HHG can "e under!tood from a !emi-cla!!ical model or three !te

2tep 3*ropagation

2tep /3 Tunnellingioni4ation

2tep53&ecom"ination

Tunion

&ecomHar

Ip

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#heory of High-order Harmonic Generatio

7inetic energy of the electron 6!inupon recom"inatio

6'in(8r) 9 Up(!in 8r: !in 8i)

6nergy of the photon emitted upon recom"ination i!

h = Ekin(r) + Ip

Ip 3 Ioni4ation potential of the atom

Up 3 *onderomotie energy

8r 3 &ecom"ination pha!e

8i 3 6mi!!ion pha!e

6'in(8r) ta'e! the ma1imum alue 5$/;Upat 8i

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5$/;

/=

#heory of High-order Harmonic Generatio

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Schematic of Higher Harmonic Genera&'(eriment from Plasma Plumes

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)uture (lan

Under!tanding the mechani!m of HHG3

>uantum mechanical model$

Under!tanding the method! to generate ultra-!hort la!

Chirp pul!e amplication method$

Characteri4ation of ultra-!hort la!er pul!e3?utocorrelation method!$

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TH?+7 @AU