Iji gbazee ihe ndị dị n'akụkụ abụọ nke njikọ ahụ n'otu oge ma guzobe njikọ mpaghara dị ike nke ukwuu, a ga-elekwasị anya na ebe a na-ahụ maka laser na ihe nlele ahụ kpọmkwem, nke na-etinye mkpa siri ike na izi ezi nke usoro ịgbado ọkụ. Na mgbakwunye, n'ihi nnukwu ike axial gradient nke Gaussian beam mgbe ọ lekọtara anya, okpomọkụ ubi focal adịghị nhata, na-eme ka ọ nwee ike ịmepụta ntụpọ micro- na nano-void na mpaghara laser metụtara, nke na-emetụta àgwà ịgbado ọkụ nke ihe nlele ahụ.
Enwere ike iji teknụzụ nhazi ọkụ oghere mepụta oghere Bessel nke na-enweghị usoro iji mee ka nkesa ike nke ubi lesa ahụ dịkwuo mma. Ụzọ a na-ebelata oke ike axial ma na-agbatị ogologo lesa ahụ, si otú a na-amụba oke omimi-ruo-obosara nke mpaghara mmetụta okpomọkụ nke lesa ahụ mepụtara. N'ihi ya, ọ na-ebelata ihe achọrọ maka izi ezi nke sistemụ ịgbado ọkụ lesa ahụ, na-eme ka mma ịgbado ọkụ na arụmọrụ dịkwuo mma.
1. Ọgbọ na Nhazi Parameter nke Bessel Beams Na-adịghị Agbanwe
Na 1987, Durnin buru ụzọ wepụta Bessel beam nke na-anaghị agbanwe agbanwe, nke na-egosi ihe pụrụ iche na-anaghị agbanwe agbanwe: ike ya na-anaghị agbanwe agbanwe n'oge mgbasa, nha nke ebe etiti ahụ na-adịkwa nso na oke mgbasa. Na mgbakwunye, Bessel beam na-egosipụtakwa ihe na-agwọ onwe ya n'oge mgbasa. Mgbe a na-egbochi ebe etiti ahụ, ìhè gbara ya gburugburu ga-agbakọta gaa n'etiti iji "rụzie" ebe etiti ahụ. Okwu mgbakọ na mwepụ maka nkesa ubi ọkụ nke Bessel beam nke na-anaghị agbanwe agbanwe bụ:
N'okwu ahụ:
- J0 na-anọchite anya ọrụ Bessel nke na-enweghị usoro.
- r na φ bụ ihe nhazi radial na angular, n'otu n'otu.
- z bụ anya mgbasa.
- Kr na Kz bụ ihe ndị na-agagharị agagharị na ndị na-agagharị ogologo oge, n'otu n'otu.
Isi ihe dị n'etiti osisi Bessel nke na-enweghị usoro efu nwere ikike njide siri ike, na-enye ohere maka ọkwa radieshon nke usoro TW/cm² ma ọ bụ karịa, nke nwere ike ịkpalite nnabata na-abụghị ahịrị n'ime ihe. Ihe kacha mkpa bụ na njirimara mgbasa nke osisi Bessel nke na-enweghị usoro efu na-enye omimi ka ukwuu nke nlebara anya na obere gradient ike axial, si otú a na-emepụta mpaghara okpomọkụ fọrọ nke nta ka ọ bụrụ otu ma na-egbochi mmepụta nke ntụpọ ịgbado ọkụ.
Foto a na-egosi ntụnyere nke ogologo focal nke Bessel beam na Gaussian beam n'okpuru otu ikike njide transverse. Bessel beam nwere nnukwu omimi nke focal level ebe ọ na-ejigide dayameta focal spot transverse micron-level.
E nwere ọtụtụ ụzọ isi mepụta beam Bessel nke na-adịghị agbanwe agbanwe, ụzọ atọ ndị a bụ isi a na-ahụkarị:
Usoro Oghere Annular: Dịka aha ya si kwuo, usoro oghere annular gụnyere iji oghere annular mepụta oghere Bessel. Nke a bụkwa ụzọ mbụ gara nke ọma maka imepụta oghere Bessel. Ihe osise dị n'okpuru na-egosi usoro oghere annular maka imepụta oghere Bessel. Ebili mmiri na-eme ka ọ dabara n'akụkụ aka ekpe ma gbasaa oghere annular site n'aka ekpe wee mee diffraction.
Mgbe nke ahụ gasịrị, oghere anya dị mma na-eme mgbanwe Fourier, na-eme ka e nwee oghere Bessel n'azụ oghere anya ahụ. Ogologo mgbasa ozi Zmax na-adịghị agbanwe agbanwe metụtara dayameta d nke oghere annular na oghere ọnụọgụgụ nke oghere anya ahụ.
Ọ bụ ezie na usoro a nwere ike imepụta ọkụ Bessel nke na-enweghị usoro, arụmọrụ mgbanwe ike dị oke ala, na-eme ka ọ sie ike itinye ya n'ọhịa nhazi laser.
Usoro Modulator Ọkụ Oghere: Usoro mmepụta nke Bessel nke na-agbanwe usoro nkesa nke osisi ahụ bụ usoro nke ịgbanwe usoro nkesa nke osisi ahụ. Ya mere, enwere ike ịmepụta Bessel nke na-agbanwe usoro nkesa nke osisi ahụ site na iji modulator ọkụ oghere. Modulator ọkụ oghere bụ ụdị ngwaọrụ optoelectronic modulation nke na-achịkwa ike nke ubi ọkụ na nkesa nke usoro site na mgbama eletriki. Enwere ike ịmepụta Bessel nke na-agbanwe usoro nke osisi ahụ site na itinye usoro lenzi conical, dịka egosiri na foto dị n'okpuru, na panel ọrụ nke modulator ọkụ oghere.
Usoro Axicon: Axicon bụ otu n'ime ihe ndị na-adịghị agbanwe agbanwe nke e ji iko mee nke a na-ejikarị emepụta ihe ndị na-adịghị agbanwe agbanwe nke Bessel. Mgbe ihe ndị na-adịghị agbanwe agbanwe na Gaussian na-emekarị ma na-agafe na axicon, a na-agbanwe nkesa nke usoro ya, na-agbanwe ya ka ọ bụrụ ihe na-adịghị agbanwe agbanwe nke Bessel na-enweghị ike ọ bụla, dịka egosiri na foto dị n'okpuru.
N'ihi ọnụ ahịa dị ala, ịdị mfe iji, na oke mmebi laser nke axicon iko, yana arụmọrụ ike dị elu ha, axicon bụ nhọrọ kachasị maka imepụta ultrashort pulse bells Bessel n'ọhịa nhazi laser. Foto dị n'okpuru na-egosi atụmatụ nke mbelata na nnyefe nke bells Bessel nke na-adịghị agbanwe agbanwe. Site na ịgbanwe mmụba na ntụzịaka nke sistemụ onyonyo 4f, enwere ike ijikwa anya mgbasa ozi na-adịghị agbanwe agbanwe, akụkụ ọkara kọne, na akụkụ ntụgharị na ntụziaka mgbasa nke bessel bears ngwa ngwa.
Mgbe oghere Bessel nke na-enweghị usoro efu nwere akụkụ ọkara kọn nke Ɵ1 na anya mgbasa nke Zmax nke na-enweghị mgbasa nke na-agafe na sistemụ 4f nke nwere oghere (L1) na oghere anya (L2), a ga-akpọchi akụkụ geometric ahụ. Mmụba n'akụkụ dị ihe dị ka M=f1/f2=5, mmụba ogologo dị ihe dị ka M2=25. Ya mere, enwere ike iji paramita geometric gosipụta onyonyo ikpeazụ nke oghere Bessel nke na-enweghị usoro efu dị n'ime ihe nlele ahụ:
E sere paramita geometric nke Bessel beam n'ime ihe nlele iko quartz n'okpuru akụkụ cone dị iche iche na mmụba nrụgide beam.
| akụkụ elu axial α (°) | Mgbada ọkụ ntinye d(mm) | (um) | M=f1/f2 | Ɵ2 (°) | Zmax2 | |
| 0.5 | 3.8 | 1.03 | 20 | 3.1 | 3504 | 10.04 |
| 0.5 | 3.8 | 1.03 | 30 | 4.7 | 1555 | 6.7 |
| 0.5 | 3.8 | 1.03 | 40 | 6.2 | 873 | 5.02 |
| 0.5 | 3.8 | 1.03 | 50 | 7.8 | 558 | 4.02 |
| 1 | 3.8 | 1.03 | 20 | 6.2 | 1747 | 5.02 |
| 1 | 3.8 | 1.03 | 30 | 9.3 | 772 | 3.36 |
| 1 | 3.8 | 1.03 | 40 | 12.4 | 432 | 2.52 |
| 1 | 3.8 | 1.03 | 50 | 15.5 | 274 | 2.04 |
| 2.5 | 3.8 | 1.03 | 20 | 15.5 | 684 | 2.04 |
| 2.5 | 3.8 | 1.03 | 30 | 23.3 | 294 | 1.38 |
| 2.5 | 3.8 | 1.03 | 40 | 38.83 | 94.4 | 0.86 |
Nkesa ike ubi lekwasịrị anya nke Bessel beam
- r na z: Ihe ndị mejupụtara nhazi radial na axial, n'otu n'otu.
- λ: Ogologo ogologo nke laser ahụ.
- w: radius 1/e² nke ihe merenụ. Ọwara Gaussian.
- P0: Ike kachasị elu nke laser pulse ultrashort.
- β1: Akụkụ ọkara kọn nke Bessel beam mgbe nrụgide osisi gasịrị.
- k: Vektọ ebili mmiri.
- J0: Ọrụ Bessel efu.
Nkesa ike nke Bessel nke na-adịghị agbanwe agbanwe n'ime iko quartz: N'aka ekpe bụ nkesa ike optical njupụta n'akụkụ ntụziaka mgbasa na echiche nke akụkụ obe, na n'aka nri bụ nkesa ike optical njupụta n'akụkụ axis na echiche nke akụkụ obe
2. Àgwà nke Femtosecond Pulse Bessel Beam na Fused Silica Glass
Foto (a) na-egosi micrograph nke mmekọrịta dị n'etiti femtosecond pulse beams Bessel na fused silica glass na ike pulse dị iche iche. A na-edozi obosara pulse laser na 220 fs, akụkụ ọkara-cone nke beam Bessel dị n'ime ihe nlele ahụ bụ 12.4°. A pụrụ ịhụ na mpaghara laser metụtara na-egosipụta nhazi linear nkịtị otu akụkụ. Mgbe ike pulse laser erughị 9.5 μJ, ihe ntụgharị uche nke ihe dị na mpaghara focal na-abawanye, na-apụta dị ka mpaghara ojii na micrograph.
Mgbe ike mkpali laser gafere 9.5 μJ, ihe na-agbanwe agbanwe nke ihe dị na mpaghara etiti na-ebelata, na-apụta dị ka mpaghara ọcha na micrograph, ogologo mpaghara ọcha na-abawanye ka ike mkpali na-abawanye. Site n'ịcha ihe nlele ahụ, anyị hụrụ njirimara ọdịdị nke mpaghara ọcha na ike mkpali nke 15.4 μJ n'okpuru igwe nyocha eletrọn, dịka egosiri na Foto (b). Enwere ike ikwubi na a na-emepụta nanopore nwere dayameta nke ihe dị ka 200 nm na mpaghara ahụ yana obere index refractive.
Site na nhazi ion beam na sistemụ nlele elektrọn microscope n'ime ebe a, anyị gosikwara na nanopore ahụ dị (Foto c). Ya mere, iji belata mmepụta nke ntụpọ laser kpatara, ike otu pulse ekwesịghị ịgafe 9.5 μJ n'oge ịgbado ọkụ laser.
3. Imezu obere ịgbado ọkụ dị elu n'etiti iko silica a gwakọtara agwakọta site na iji Bessel Ultrashort Pulse Laser.
Foto (a) na-egosi obere onyonyo elu nke elu njikọta ihe nlele ahụ. A pụrụ ịhụ na eriri njikọta laser ahụ dị otu ma dị ire ụtọ. Ọ bụ ezie na enwere obere ntụpọ obere oghere dị iche iche a na-ekesa n'ụzọ na-enweghị usoro na mpaghara njikọta ahụ, n'ozuzu ya, ọ ka mma nke ukwuu karịa eriri njikọta laser Gaussian. Nha na-egosi na obosara nke eriri njikọta ahụ dị ihe dị ka 18 μm, oghere dị n'etiti ahịrị njikọta ahụ bụkwa 40 μm. Foto (b) na-egosi obere onyonyo akụkụ nke ahịrị njikọta nke ihe nlele ahụ.
A pụrụ ịhụ na oghere dị n'etiti ihe nlele ahụ na-apụ n'anya kpamkpam mgbe a rụchara ọrụ laser, ihe ndị dị nso na njikọ ahụ ejikọtala n'otu ihe mgbe ha mechara usoro ịgbaze okpomọkụ na-eme ka mmiri dị jụụ. Ntụle ndị a na-egosi na omimi nke mpaghara ịgbaze okpomọkụ nke laser kpatara ruru 227 μm. Nke a na-egosi na n'oge ịgbaze laser na paramita ndị a, omimi axial nke ọnọdụ focal nwere ike iru ruo 227 μm, nke bụ okpukpu anọ nke ịgbaze laser Gaussian n'okpuru otu ọnọdụ ahụ.
4. Ebee ka ị ga-azụta anya Bessel?
Opto-Electronic Wavelength nwere anya Bessel dị elu nke a na-eji eme ihe n'ịhazi laser. Ịgbanwe omimi nke ihe na-eme ka ihe pụta ìhè site n'ịhazi nha nke dayameta ihe na-abanye bụ ihe kacha mma na sistemụ anya Bessel a.
| Nkebi Nke | Ogologo ebili mmiri (nm) | Ogologo Ọrụ (mm) | Dia Mbupu Ntinye Kachasị Elu (mm) | Omimi nke Nlekwasị Anya Emebere (mm) | Ogologo zuru oke (mm) |
|---|---|---|---|---|---|
| BESL-355-D10-T1 | 355 | 15.50 | 10 | 1.0 | 377.00 |
| BESL-532-10-D10 | 532 | 11.86 | 10 | 1.5 | 202.84 |
| BESL-1064-D10-T2 | 1064 | 10.80 | 10 | 2.0 | 238.00 |
| BESL-1064-D20-T12 | 1064 | 15.00 | 20 | 12.0 | 315.05 |
Oge ozi: Ọktoba-10-2024