{"product_id":"dicka-superradiance","title":"Dicka – Dicke Superradiance \/ I ∝ N² Physics Sticker","description":"\u003cp\u003eDicka, a choir of glowing atoms in unison, sings one blinding note where a crowd of soloists would only hum.\u003c\/p\u003e\u003ch3\u003eThe Physics\u003c\/h3\u003e\u003cp\u003eN excited atoms that radiate independently give N times the light of one. But if they are packed close together, within about a wavelength, or otherwise coupled to the same light field, they can lock into phase and radiate as one giant dipole. Then the peak intensity grows as N², and the light comes out in a short, bright burst. Robert Dicke predicted this in “Coherence in Spontaneous Radiation Processes” (Phys. Rev. 93, 99, 1954).\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eI\u003csub\u003epeak\u003c\/sub\u003e ∝ N²\u003c\/strong\u003e\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003eI\u003csub\u003epeak\u003c\/sub\u003e: peak emitted intensity (W)\u003c\/li\u003e\n\u003cli\u003eN: number of emitters radiating in phase\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003eThe total energy released is still N photons' worth. Because the intensity is about N times higher, the burst is about N times shorter than the emission time of a single atom in the ideal model.\u003c\/p\u003e\u003cp\u003e\u003cem\u003eHonest caveat:\u003c\/em\u003e Independent emitters give I ∝ N; the N² law holds only when the emitters stay in phase. In real samples dephasing, atom motion and the sample's size and shape reduce the effect.\u003c\/p\u003e\u003ch3\u003eOn the sticker\u003c\/h3\u003e\u003cp\u003eDicka opens her mouth in song as a ring of violet atoms flashes together in her hands. Printed text: \u003cstrong\u003eDICKA\u003c\/strong\u003e with the line \u003cstrong\u003eI ∝ N²\u003c\/strong\u003e. Pixel-art kiss-cut vinyl sticker, white, in 2″, 3″, 4″ and 6″ sizes.\u003c\/p\u003e","brand":"Printify","offers":[{"title":"2\" × 2\" \/ White","offer_id":50963842990183,"sku":"96126312092521297610","price":4.99,"currency_code":"USD","in_stock":true},{"title":"3\" × 3\" \/ White","offer_id":50963843022951,"sku":"27486860967554002596","price":6.99,"currency_code":"USD","in_stock":true},{"title":"4\" × 4\" \/ White","offer_id":50963843055719,"sku":"10210941854918372448","price":8.99,"currency_code":"USD","in_stock":true},{"title":"6\" × 6\" \/ White","offer_id":50963843088487,"sku":"17860047188211448452","price":11.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0596\/8746\/9159\/files\/15041320347311792574_1200.jpg?v=1793655505","url":"https:\/\/pixelatedphysics.com\/fr\/products\/dicka-superradiance","provider":"Pixelated Physics","version":"1.0","type":"link"}