Ihiwe - a ... coherent ìhè mmiri na ebili mmiri. temporal coherence

Tụlee a-efegharị efegharị yiri na ohere. Ihiwe - a ka ọtùtù nke mmekọrịta dị n'etiti ya n'ụzọ, tụrụ na dị iche iche ihe. Ihiwe-efegharị efegharị na-adabere na e ji mara ya isi.

Abụọ na ụdị coherence

Ka anyị tụlee a dị mfe ihe atụ. Kere abụọ n'elu mmiri, na-ebili na-ada na mmiri n'elu. Iche na-efegharị efegharị iyi bụ naanị osisi nke harmonically mikpuru na wepụrụ mmiri na-agbasa udo n'elu mmiri n'elu. N'ihi ya, ọ a zuru okè mmekọrịta dị n'etiti ngagharị nke abụọ floats. Ha enweghị ike ime na ala kpomkwem ke adọ, mgbe otu onye na-aga, ndị ọzọ ala, ma ndị na-adọ dị iche n'etiti ọnọdụ nke abụọ floats bụ mgbe niile na oge. Harmonically oscillating mgbe isi iyi na-arụpụta nnọọ coherent ife.

Mgbe na-akọwa coherence nke ìhè mmiri na ebili mmiri, ịmata ihe dị iche ya abụọ na ụdị - gbasara ohere na temporal.

Ihiwe na-ezo aka ike nke ìhè na-emepụta ihe na nnyonye anya ụkpụrụ. Ọ bụrụ na abụọ ìhè mmiri na ebili mmiri na-ada ọnụ, ha na-adịghị ike ebe nke ụba na-ebelata ihie, na-akpọ ha incoherent. Ọ bụrụ na ha na "ezigbo" nnyonye ụkpụrụ (n'echiche nke zuru ezu na-ebibi nnyonye anya ebe), ha n'ụzọ zuru ezu coherent. Ọ bụrụ na abụọ mmiri na ebili mmiri nke ike "na-erughị zuru okè" picture, ọ na-atụle na ha bụ ndị na-ezughị ezu coherent.

Michelson interferometer

Ihiwe - a onu na a na-kacha mma kọwara otu onye na nnwale.

Na Michelson interferometer ìhè isi iyi S (nke nwere ike ịbụ ihe ọ bụla nke: anyanwụ, kpakpando, ma ọ bụ laser) na-eduzi jidesie a semitransparent mirror M _0, nke na-anọchite anya 50% nke ìhè kwupụta mirror M ₁ na Site n'ibu 50% kwupụta mirror M _2. The doo Imokụt n'ebe onye ọ bụla nke enyo azụ M _0, na hà òkè nke ìhè gosipụtara si M ₁ na M _{2 na-jikọtara} na atumatu olu jidesie a ihuenyo B. The ngwaọrụ nwere ike ahazi site na-agbanwe anya si mirror M ₁ doo splitter.

Michelson interferometer nnoo mixes doo na oge-egbu oge version nke ya. Ìhè na-aga n'ụzọ ka mirror M ₁ nwere na-aga n'ebe dị anya na 2D karịa a doo na-akpali mirror M _2.

Ogologo na coherence oge

Gịnị a hụrụ na ihuenyo? Mgbe d = 0 nwere ike hụrụ ọtụtụ doro nnọọ anya na nnyonye fringes. Mgbe d na-amụba, na ìgwè na-aghọ obere akpọ: ọchịchịrị ebe ayama, na ìhè - dimmer. N'ikpeazụ, n'ihi na dị nnọọ nnukwu d, uku a ụfọdụ oké egwu uru nke D, na ìhè na ọchịchịrị yiri mgbaaka na-apụ n'anya kpamkpam, na-ahapụ nanị a blur.

N'ụzọ doro anya, ìhè ubi nwere ike adịghị egbochi oge-egbu oge version nke ya onwe ya mgbe oge na-egbu oge bụ nnukwu iji. Anya 2D - ọ bụ coherence ogologo: nnyonye anya mmetụta ndị kwesiri ngosi naanị mgbe ihe dị iche n'ụzọ na-erughị nke a anya. Nke a bara uru nwere ike ghọrọ n'oge t _c ya nkewa site ọsọ nke ìhè c: t _c = 2D / c.

Michelson nnwale jikoro temporal coherence nke ìhè-efegharị efegharị: ike igbochi a na-egbu oge version nke ya onwe ya. A ọma-Nọsi'ike laser t _c = 10 ^-4 s, l _c = 30 km; ẹdụk ìhè si okpomọkụ t _c = 10 ^-8, l _c = 3 m.

Ihiwe na oge

Na ɛhe coherence - a ọtụtụ nke mmekọrịta dị n'etiti ndị n'ụzọ nke ìhè mmiri na ebili mmiri dị iche iche ihe tinyere ịnọgide direction.

Iche iyi ewepụtarịrị a wavelength nke λ na λ ± Δλ, nke na ụfọdụ ná ohere ga egbochi na a anya l _c = λ ² / (2πΔλ). Ebe l _c - coherence n'ogologo.

The na-adọ nke a-efegharị efegharị yiri na x direction na a kọwara dị ka f = kx - ωt. Ọ bụrụ na anyị na-atụle Ọgụgụ mmiri na ebili mmiri na mbara igwe na oge t na a anya l _c, ndị na-adọ dị iche n'etiti abụọ ife Vektọ k ₁ na k _2, nke na-na-adọ na x = 0 bụ hà Δφ = l _c (k ₁ - k _2). Mgbe Δφ = 1, ma ọ bụ Δφ ~ 60 Celsius, ìhè bụ agaghịkwa coherent. Nnyonye anya na diffraction nwere ịrịba utịp ke iche.

N'ihi ya:

• 1 = l _c (k ₁ - k _{2) = l c (2π / λ} - 2π / (λ + Δλ));
• _{l c (λ + Δλ - λ} ) / (λ (λ + Δλ)) ~ l c Δλ / λ ² = 1 / 2π;
• l _c = λ ² / (2πΔλ).

The-efegharị efegharị na-aga site na ohere na a ike ọsọ c.

The coherence oge t _c = l _c / s. Ebe ọ bụ na λf = c, mgbe ahụ, Δf / f = Δω / ω = Δλ / λ. Anyị nwere ike ide

• l _c = λ ² / (2πΔλ) = λf / ( 2πΔf) = c / Δω;
• t _c = 1 / Δω.

Ọ bụrụ na a mara wavelength ma ọ bụ ugboro nke Mgbasa nke ìhè isi, ọ bụ omume na-gbakọọ l _c na t _c. Ọ gaghị ekwe omume na-edebe nnyonye ụkpụrụ nwetara site nkerisi njupụta, dị ka mkpa film nnyonye anya, ma ọ bụrụ na ngwa anya ụzọ dị iche bụ budata ukwuu karịa l _c.

Na ɛhe coherence akwụkwọ na-ekwu Black.

Ihiwe na ohere

Gbasara ohere coherence - a ọtụtụ nke mmekọrịta dị n'etiti ndị n'ụzọ nke ìhè mmiri na ebili mmiri dị iche iche ihe transverse nduzi nke Mgbasa.

Mgbe anya L si monochromatic thermal (linear) iyi onye linear akụkụ nke iji nke δ, abụọ ohere mpere dị na a anya ukwuu karịa d _c = 0,16λL / δ, agaghịkwa emepụta a recognizable nnyonye ụkpụrụ. πd _c ^2/4 bụ nke ebe coherence isi iyi.

Ọ bụrụ na oge t ahụ isi iyi nke obosara δ, ewekarị perpendicular anya L si ihuenyo, na ihuenyo pụrụ ịhụ abụọ ihe (P1 na P2), iche site na a anya d. The electric ubi na P1 na P2-anọchi anya superposition nke electric ubi nke mmiri na ebili mmiri enwupụta niile isi nke isi iyi, na ụzarị ọkụ nke na-abụghị onye ọ bụla ọzọ. Iji akpa ebili mmiri exiting P1 na P2, eke a recognizable nnyonye nlereanya superposition P1 na P2 kwesịrị ịbụ na-adọ.

coherence ọnọdụ

Light ebili mmiri nwetara site abụọ n'ọnụ nke isi iyi, ụfọdụ ebe nke oge t nwere ihe ụfọdụ na-adọ iche ozugbo na center n'etiti abụọ ihe. The doo na-abịa site n'aka ekpe ọnu δ ka a mgbe P2 ruo d (sinθ) / 2 gbadakwuo karịa doo-aga center. The trajectory nke okporo osisi na-abịa site nri ihu δ tụọ P2, na-aga na ụzọ d (sinθ) / 2 obere. The dị iche na anya gara abụọ ibé na-d · sinθ na-anọchite anya ndị na-adọ iche Δf '= 2πd · sinθ / λ. N'ihi na anya si P1 na P2 tinyere na-efegharị efegharị n'ihu, anyị na-enweta Δφ = 2Δφ '= 4πd · sinθ / λ. Mmiri na ebili mmiri enwupụta abụọ n'ọnụ nke isi iyi, na-na-adọ na P1 na oge t na ndị nke na-adọ na mpaghara 4πdsinθ / λ na P2. Ebe ọ bụ na sinθ ~ δ / (2L), mgbe ahụ Δφ = 2πdδ / (Lλ). Mgbe Δφ = Δφ ~ 1 ma ọ bụ 60 Celsius, ìhè na-agaghịkwa atụle coherent.

Δφ = 1 -> d = Lλ / (2πδ) = 0,16 Lλ / δ.

The gbasara ohere coherence nke kwuru wavefront adọ homogeneity.

Incandescent oriọna bụ ihe atụ nke incoherent ìhè isi.

Coherent ìhè nwere ike enwetara site na a isi iyi nke incoherent radieshon, ma ọ bụrụ na anyị na-tụfuo kasị nke radieshon. The mbụ gbasara ohere nzacha na rụrụ dịkwuo gbasara ohere coherence, wee spektral nzacha n'ihi na ibu temporal coherence.

Fourier usoro

Sinusoidal ụgbọelu efegharị efegharị kpamkpam coherent na ohere na oge, na ya ogologo oge na coherence ebe-adịghị agwụ agwụ. All ezigbo ebili mmiri na-efegharị efegharị pulses na-adịgide adịgide maka a nwere oke nkeji oge, na-enwe ọgwụgwụ perpendicular ka ha ntụziaka nke ịnọgide. Mathematically, a kọwara ha site a nke oge ọrụ. Iji chọta frequencies ugbu a na-efegharị efegharị pulses na-ekpebi a coherence ogologo Δω mkpa iji nyochaa na-abụghị oge ọrụ.

Dị ka Fourier analysis, na-ezighị ezi oge ife nwere ike na-ahuta ka a superposition nke enweghị mmiri na ebili mmiri. Fourier njikọ pụtara na superposition nke a plurality nke sinusoidal mmiri na ebili mmiri na-enye ohere iji nweta aka ike nke oge waveform.

Communication ọnụ ọgụgụ

Ihiwe ozizi nwere ike ga-atụle ka njikọ nke physics na nkà mmụta ndị ọzọ, ebe ọ bụ n'ihi nke a mmakọ nke akpa ozizi na ndekọ ọnụ ọgụgụ, nakwa dị ka mgbakọ na mwepụ na-arụzi ụgbọala bụ njikọ nke ọnụ ọgụgụ na-arụzi ụgbọala. Ozizi a na-eji gụpụta ndị e ji mara na mmetụta nke random fluctuations na omume nke ìhè ubi.

Na-emekarị na ọ bụ omume tụọ fluctuations na-efegharị efegharị ubi ozugbo. Onye "lee njem" anya ìhè na-apụghị ahụrụ ozugbo, ma ọ bụ ọbụna na ọkaibe ngwá: ya ugboro bụ mkpokọta October ¹⁵ oscillations kwa nke abụọ. Ị nwere ike na-tụọ averages.

Ngwa nke coherence

Njikọ nke physics na nkà mmụta ndị ọzọ dị ka ihe atụ coherence ike deere na a ọnụ ọgụgụ nke ngwa. Ikpe coherent ubi na-na-erughị emetụta ikuku ịgbā, nke na-eme ka ha bara uru n'ihi na laser na nkwukọrịta. Ha na-eji na-amụ laser na-akpata anọ na Jeremaya mere: a Mbelata nnyonye anya mmetụta na-eduga na "ire ụtọ" ihe nke doo na ite lekwasịrị. Ihiwe na-eji na akpan akpan na-ekpebi size na oke nke kpakpando ọnụọgụ abụọ na usoro.

Ihiwe nke ìhè mmiri na ebili mmiri na-arụ ọrụ dị mkpa ọmụmụ nke kwantum na oge gboo ubi. Na 2005, Roy J. Glauber ghọrọ otu n'ime ndị mmeri nke Nobel chọr'inwe na Physics maka ya onyinye kwantum ozizi ngwa anya coherence.